Upload
tamra
View
91
Download
2
Embed Size (px)
DESCRIPTION
看不見的手 : 市場結構與市場力量. 江淳芳 2014/4/23. 自我介紹. 1995 北一女畢業 1999 台大數學畢業 2001 台大經研所畢業 工作兩年, 2003 出國到 Brown University 2008 Econ Ph.D. 在台大任教至今 研究領域:政治經濟學 健康經濟學 實證經濟學. 什麼是經濟學?. 研究理性個人如何作決策的社會科學 早餐要到餐廳或牛角坡?買三明治、蘿蔔糕、 或蛋餅? 台積電是否到大陸投資? 政府是否要開辦老人年金? 如何提高就業率、國民所得? 人為什麼要做決策 ?. - PowerPoint PPT Presentation
Citation preview
看不見的手 市場結構與市場力量
江淳芳2014423
自我介紹 1995 北一女畢業 1999 台大數學畢業 2001 台大經研所畢業 工作兩年 2003 出國到 Brown University 2008 Econ PhD 在台大任教至今 研究領域政治經濟學 健康經濟學 實證經濟學
什麼是經濟學 研究理性個人如何作決策的社會科學
早餐要到餐廳或牛角坡買三明治蘿蔔糕 或蛋餅 台積電是否到大陸投資 政府是否要開辦老人年金 如何提高就業率國民所得
人為什麼要做決策
稀少 SCARCITY 資源有限而慾望無窮 「相對性」的概念
窮人與富人都面對「資源稀少」的問題 資源稀少卻有多種用途 「家家有本難念的經」
經濟行為就是「選擇」的行為 如何利用稀少的資源達成最大的福祇
學經濟學可以幫助我們什麼 經濟學的理論是思考的工具它不是教條所以不會提供可以立即應用在政策的結論而是一套方法能幫助其使用者推導出正確的結論 John Maynard Keynes
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
自我介紹 1995 北一女畢業 1999 台大數學畢業 2001 台大經研所畢業 工作兩年 2003 出國到 Brown University 2008 Econ PhD 在台大任教至今 研究領域政治經濟學 健康經濟學 實證經濟學
什麼是經濟學 研究理性個人如何作決策的社會科學
早餐要到餐廳或牛角坡買三明治蘿蔔糕 或蛋餅 台積電是否到大陸投資 政府是否要開辦老人年金 如何提高就業率國民所得
人為什麼要做決策
稀少 SCARCITY 資源有限而慾望無窮 「相對性」的概念
窮人與富人都面對「資源稀少」的問題 資源稀少卻有多種用途 「家家有本難念的經」
經濟行為就是「選擇」的行為 如何利用稀少的資源達成最大的福祇
學經濟學可以幫助我們什麼 經濟學的理論是思考的工具它不是教條所以不會提供可以立即應用在政策的結論而是一套方法能幫助其使用者推導出正確的結論 John Maynard Keynes
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
什麼是經濟學 研究理性個人如何作決策的社會科學
早餐要到餐廳或牛角坡買三明治蘿蔔糕 或蛋餅 台積電是否到大陸投資 政府是否要開辦老人年金 如何提高就業率國民所得
人為什麼要做決策
稀少 SCARCITY 資源有限而慾望無窮 「相對性」的概念
窮人與富人都面對「資源稀少」的問題 資源稀少卻有多種用途 「家家有本難念的經」
經濟行為就是「選擇」的行為 如何利用稀少的資源達成最大的福祇
學經濟學可以幫助我們什麼 經濟學的理論是思考的工具它不是教條所以不會提供可以立即應用在政策的結論而是一套方法能幫助其使用者推導出正確的結論 John Maynard Keynes
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
稀少 SCARCITY 資源有限而慾望無窮 「相對性」的概念
窮人與富人都面對「資源稀少」的問題 資源稀少卻有多種用途 「家家有本難念的經」
經濟行為就是「選擇」的行為 如何利用稀少的資源達成最大的福祇
學經濟學可以幫助我們什麼 經濟學的理論是思考的工具它不是教條所以不會提供可以立即應用在政策的結論而是一套方法能幫助其使用者推導出正確的結論 John Maynard Keynes
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
學經濟學可以幫助我們什麼 經濟學的理論是思考的工具它不是教條所以不會提供可以立即應用在政策的結論而是一套方法能幫助其使用者推導出正確的結論 John Maynard Keynes
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
經濟學的訓練 並不是要讓你牢記一大堆理論與模型 而是希望學生能夠學習思考推理的方法 擁有一套基本的分析工具
當你面對五花八門的社會現象與繁雜的公共政策辯論時 能夠提出一個異於一般社會大眾的獨到經濟學見解 修習經濟學後 對於以下的諸多問題 你可能會有不同的體會與心得 例如台灣發生 SARS 疫情時 口罩那裡去了 油蟲哪裡來 多元入學了 為什麼壓力還是那麼大 流浪教師哪裡來
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
TODAY 市場 市場結構 市場效率 什麼是市場 實驗 自由競爭市場背後看不見的手 什麼是經濟學家常常在提的效率 經濟模型 以房屋市場為例 獨占市場與完全競爭市場有什麼不同 市場有可能失靈嗎 人與人之間的交易與國與國之間的貿易
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
為什麼經濟學家常常強調市場機制 市場是什麼 市場有什麼了不起
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
什麼是市場 Caroline Hoxby Harvard University ldquoA market is fundamentally a place in which
people make exchanges when we say a market we generally mean that the exchanges are governed by prices
That prices changing are the method by which goods and services are allocated from one person to another or that prices are the means by which goods and services are rationed rdquo
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
什麼是市場 市場起源於古時人類對於固定時段或地點進行交易的場所的稱呼而此交易場所是那些需要經常進行物品交換的人為了減少搜尋成本所自發形成的詞中的ldquo市rdquo 指的並非ldquo城市rdquo而是古時的ldquo買賣rdquoldquo交易rdquo之意 今日市場具備了兩種意義一個意義是交易場所如傳統市場股票市場期貨市場等等另一意義為交易行為的總稱 市場一詞不僅僅只是場所還包括了在此場所進行交易的行為故當談論到市場大小時並不僅僅指場所的大小還包括了消費行為是否活躍 廣義上所有產權發生轉移和交換的關係都可以成為市場
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET ECONOMICS ARE DECENTRALIZED After all market economies are
decentralized There are thousands of buyers and thousands of sellers in many markets
Why doesnrsquot this decentralized economy generate complete chaos
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET IS A GOOD PLACE TO ALLOCATE RESOURES We call our system a market economy
because itrsquos made up of huge numbers of markets like this one
Resources are allocated through the decisions of millions of firms and millions of households
-- Firms decide what to make and who to hire -- Individuals decide who to work for and how
to spend their income -- Everyone interacts in the market place
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
ADAM SMITH (1723-1790) Well Adam Smith said that the markets in
fact work very well He said that they are guided as if by an
invisible hand and leads to desirable allocation of resources
One of the reasons to study economics is to understand how that invisible hand works how it is that buyers and sellers interact with one anotherhellipcould be a chaotic setting and leads to a desirable outcome
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
INVISIBLE HAND 在市場上每個人都追逐私利但就好像存在一雙「看不見的手」讓追逐私利的行為自動變成促進公共利益的力量 競爭性的市場就是「看不見的手」 市場的魔力將潛在是「惡」的力量便成了最大的「善」 赤裸裸的貪婪自私帶來的是企業效率的提高創新自動轉化為促進社會利益的行為
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
How does the invisible hand work its magic How does it lead market to desirable
outcome
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
什麼是市場 我們需要哪兩個元素形成市場
市場 買方賣方
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
買方 ( 消費者 ) 買方的主要目的是 -- 獲得商品及服務 -- 以最好的價格 對於某一商品 ex 綠色軍外套 心中會設定一個最高願意支付的金額
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
買方 (BUYER)
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
在市場上有很多消費者大家和我一樣對此商品都有自己的評價 ( 最高願意支付的金額 )
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
賣方 (SELLER) 賣方想要 -- 出售他們的商品及服務 -- 賣越貴越好
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
賣方 ( 生產者 ) 你有最低願意出售的金額 而且你會接受任何高於這個最低願售金額的價格
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
賣方 ( 生產者 ) 在市場上有很多賣家大家對此商品都有自己願意出售的金額當然所有賣家都希望價格越高越好
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
市場價格怎麼來的呢 市場的最高價格由整個市場中對此商品具最高評價的消費者所決定因為高於這個價格市場上就沒人願意買商品
市場的最低價格hellip
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
需求曲線 DEMAND CURVE 需求量 -- 給定價格市場上的消費者願意買多少單位
在不同價格下需求量會不同需求也就是說價格與需求量的關係若以圖像表示便稱為「需求曲線」
從願付價格高的人排到願付價格低的人
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
需求曲線 DEMAND CURVE
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
SUPPLY供給 (supply) 指的是供給量 (quantity supplied) 與價格之間的價量關係
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
市場均衡 在某個價格下 此商品的供給量與需求量相等
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXPERIMENT Buyers or Sellers Aim to maximize your profit
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
實驗數據 Buyers 願付價格 70 60 50 30 20
成本價格 10 20 30 50 60 70
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
DEMAND AND SUPPLY IN THE EXPERIMENT
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
How does the invisible hand work its magic How does it lead market to desirable
outcome
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PRICE PRICE AND PRICE Well turns up the prices are the key
instrument
Prices are what signal to buyers what to buy and prices are signals to sellers how much to produce and sell
價格就像看不見的手拿的指揮棒
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
WHICH OUTCOMES ARE DESIRABLE 如果沒有市場hellip如果使用抽籤hellip
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
從實驗到真實世界再到經濟模型 有什麼不同
什麼情況下價格可能會改變
Economic Modeling
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
ECONOMIC MODELING What causes what in economic systems
At what level of detail shall we model an economic phenomenon
Which variables are determined outside the model ( 外生給定 ) and which are to be determined by the model ( 內生 )
35
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLE 天龍國內的小套房租屋市場 建一個模型討論小套房的房租 Assumptions
apartments are close or distant ( 想像天龍國被山包圍 住在山的另一邊相對遙遠 ) 所有小套房長的都一樣遠距離的小套房的房租是固定 已知的 ( 外生給定 ) 有許多房東也有許多想租房的房客
36
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MODELING THE APARTMENT MARKET Questions-- Who will rent close apartments-- At what price-- Will the allocation of apartments be desirable in
any sense
How can we construct an insightful model to answer these questions
37
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
分析方法上的假設 Two basic principles
Rational Choice(The optimization principle) Each person tries to choose the best alternative available to him or her
Equilibrium Market price adjusts until quantity demanded equals quantity supplied
38
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MODELING APARTMENT DEMAND Demand -- 給定價格市場上的消費者願意買多少單位 -- 每個人的願付價格是多少
39
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
40
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MODELING APARTMENT DEMAND The lower is the rental rate p the larger is
the quantity of close apartments demandedp QD
The quantity demanded vs price graph is the market demand curve for close apartments
41
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET DEMAND CURVE FOR APARTMENTS
p
QD
42
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MODELING APARTMENT SUPPLY Supply
It takes time to build more close apartments so in this short-run the quantity available is fixed (at say 100)
43
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET SUPPLY CURVE FOR APARTMENTS
p
QS10044
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡 ldquolowrdquo rental price quantity demanded of
close apartments exceeds quantity available price will rise
ldquohighrdquo rental price quantity demanded less than quantity available price will fall
45
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡 Quantity demanded = quantity available
price will neither rise nor fall so the market is at a competitive equilibrium
46
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡p
QDQS10047
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡p
QDQS
pe
10048
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
49
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡p
QDQS
pe
100
People willing to pay pe for close apartments get closeapartments
People not willing to pay pe for close apartments get distant apartments
50
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全競爭市場下的均衡 Q Who rents the close apartments A Those most willing to pay Q Who rents the distant apartments A Those least willing to pay So the competitive market allocation is by
ldquowillingness-to-payrdquo
51
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
這個模型可以幫助我們做政策分析嗎 What is exogenous in the model
price of distant apartments quantity of close apartments incomes of potential renters
What happens if these exogenous variables change
52
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
當環境 外在變數改變的時候hellip Suppose the price of distant apartment rises Demand for close apartments increases
(rightward shift) causing a higher price for close apartments
53
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
10054
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand
55
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher demand causes highermarket price same quantitytraded
56
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
當供給改變hellip Suppose there were more close apartments Supply is greater so the price for close apartments falls
57
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
10058
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS100
Higher supply
pe
59
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher supply causes alower market price and alarger quantity traded
60
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
當所得增加hellip Suppose potential rentersrsquo incomes rise
increasing their willingness-to-pay for close apartments
Demand rises (upward shift) causing higher price for close apartments
61
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
10062
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-pay
63
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET EQUILIBRIUMp
QDQS
pe
100
Higher incomes causehigher willingness-to-payhigher market price andthe same quantity traded
64
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
課稅政策的分析 Local government taxes apartment owners What happens to
price quantity of close apartments rented
Is any of the tax ldquopassedrdquo to renters 對房東課稅會不會使得房租上升
65
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
TAXATION POLICY ANALYSIS Market supply is unaffected Market demand is unaffected So the competitive market equilibrium is
unaffected by the tax Price and the quantity of close apartments
rented are not changed Landlords pay all of the tax
66
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
其他市場的課稅效果珍珠奶茶的市場需求線類似 價格越高購買的人越少供給線 假設一杯成本 50 元 (成本 原料 人力) 可以無限量供應均衡價格每賣出一杯要給政府 10 元均衡價格
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
珍珠奶茶的市場p
D(p) S(p)
Marketdemand
Marketsupply
p=50
q
No tax
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p=65
q
No tax
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
考慮一般的供給線p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tAn excise taxraises the marketsupply curve by $t
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
An excise taxraises the marketsupply curve by $traises the buyersrsquoprice and lowers thequantity traded
$tpb
qt
And sellers receive only ps = pb - t
ps
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps Tax paid by sellers
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
QUANTITY TAXES amp MARKET EQUILIBRIUM
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
pbpb
qt
pb
ps
Tax paid by buyers
Tax paid by sellers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
TAX INCIDENCE AND OWN-PRICE ELASTICITIES
p
D(p) S(p)
Marketdemand
Marketsupply
p
q
$tpb
qt
ps
As market demandbecomes less own-price elastic taxincidence shifts moreto the buyers
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
市場結構 Market structure ndash identifies how a market
is made up in terms of The number of firms in the industry The nature of the product produced The degree of monopoly power each firm has The extent of barriers to entry
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET STRUCTURE
More competitive (fewer imperfections)
Perfect Competition Pure
Monopoly
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
Market Structure
Less competitive (greater degree of imperfection)
Perfect Competition Pure
Monopoly
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
完全獨佔 (PURE MONOPOLY)獨佔市場中只有一個賣家 市場上無相似的商品 (替代品 )甚麼原因導致獨佔呢
市場有進入障礙專利 政府授權許可獨家的生產要素技術 大規模經濟
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
自然獨佔 (NATURAL MONOPOLY) 由於地理環境的自然因素或最適規模的關係而發生的
市場獨佔狀況稱為自然獨佔 1 地理環境的自然因素擁有其他地區沒有的天然資源
而形成獨佔現象例如智利產的硝石或是南洋產的橡膠 2 產業具規模經濟特性若由一家廠商生產便足以供應整個市場所需且生產成本較低但如果有兩家或數家廠商同時供應市場其成本反而提高例如電力瓦斯水力鐵路等
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
獨佔 VS 完全競爭市場 獨佔市場
價格制定者唯一賣家 市場需求線為負斜率的曲線
完全競爭市場 價格接受者 市場上有很多賣家面臨水平的市場需求曲線
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
獨佔 VS 完全競爭市場獨佔者所面臨的需求曲線為負斜率的曲線而非水平
的需求曲線
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
HOW SHOULD A MONOPOLY PRICE 獨佔者如何訂價 獨佔者主要目的是極大化銷售利潤
利潤=銷售收入 - 生產成本 獨占廠商是價格的制定者而非價格的接受者所以獨佔者可藉由調整銷售 ( 生產 ) 數量進而改變售價
若獨佔廠商增產 數量效果產量增加rarr銷售收入增加 價格效果產量增加商品價格下跌rarr銷售收入減少
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
1 單一訂價獨佔者對每個消費者皆收取同一價格 2 價格歧視 (差別訂價 ) 指販賣同一個商品但因為消費者不同或因為消費者購買數量不同而有不同的售價
為何要差別訂價銷售策略唯有當廠商具備決定價格的市場力量才會有
價格策略的產生增加利潤
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLES電影票價有全票優待票 ( 學生軍警孩童 ) 早
場票
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLES餐廳不同用餐時間價格不同 (午餐晚餐例假日 )
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLES 高鐵的早鳥優惠 (65折 8折 9折 )
愈早訂位者愈有機會訂得 65折優惠車票早鳥 65折銷售完畢即改發售早鳥 8折早鳥 8折銷售完畢即改發售早鳥 9折早鳥 9折銷售完畢即提前截止並改發售原價車票
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLES報章雜誌上的商品折價券網路上的優惠券
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
EXAMPLES貴賓卡
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
其他訂價策略 成套式定價 (bundle pricing) 指兩種以上商品合併在一款產品販售 以較低的整體價格刺激購買或促銷消費者本來不太可
能購買的商品 (Eg 速食套餐 ) 促使消費者購買成套產品以製造套牢效果 (Eg
Microsoft Office)
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
獨佔的電影院市場 ( 一 )假設電影院有獨佔市場的力量電影院將會把票價訂
在可獲得最大利潤的價格狀況一
市場共 20 個消費者每個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
電影的需求與供給 問題假若電影票只能單一訂價電影院應將票價訂
在hellip才可獲得最多利潤 (收入 - 成本 )
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
利潤極大化 (單一訂價 ) 電影票價訂在 $200 電影院能獲得最大利潤
$800 價格 (P) 成本 數量 (Q) 利潤350 100 1 250
300 100 2 400
250 100 4 600
200 100 8 800
150 100 14 700
100 100 17 0
50 100 20 -1000
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
獨佔的電影院市場 (二 ) 同上一個電影院的例子電影院有獨佔市場的力量電影院將會把票價訂在可獲得最大利潤的價格
狀況二 假設電影院可區別消費者為學生或上班族並且可以針對不
同群消費者訂不同的票價 ( 學生票全票 ) 電影市場的 20 個消費者其中有 8 個學生及 12 個上班族每
個消費者對電影票的最高願付價格 $350 $300 $250 $200 $150 $100 $50
電影票的成本為 $100
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
學生上班族對電影的需求 問題電影院若能對兩群消費者分別訂不同的票價則電影院應將學生票全票的價格訂在hellip才可獲得最大利潤
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
利潤極大化 ( 價格歧視 ) 學生票訂在 $150 全票訂在 $200 則電影院能
獲得最大利潤 $150+$700=$850 學生票價 (P) 成本 數量 (Q) 利潤
350 100 0 0300 100 0 0250 100 0 0200 100 1 100150 100 3 150100 100 5 050 100 8 -400
上班族票價 (P) 成本 數量 (Q) 利潤350 100 1 250300 100 2 400250 100 4 600200 100 7 700
150 100 11 550100 100 12 050 100 0 0
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
其他策略 商務艙與經濟艙 完全差別取價
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
回到房屋市場 -- MONOPOLYp
QD
Lowprice
Low price high quantitydemanded low revenue
101
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Highprice
High price low quantitydemanded low revenue
102
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MONOPOLISTIC MARKET EQUILIBRIUMp
QD
Middleprice
Middle price medium quantitydemanded larger revenue
103
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100104
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MONOPOLISTIC MARKET EQUILIBRIUMp
QDQS
Middleprice
Middle price medium quantitydemanded larger revenueMonopolist does not rent all theclose apartments
100
Vacant close apartments
105
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PERFECTLY DISCRIMINATORY MONOPOLISTIC LANDLORD Imagine the monopolist knew everyonersquos
willingness-to-pay Charge $500 to the most willing-to-pay charge $490 to the 2nd most willing-to-pay
etc
106
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
DISCRIMINATORY MONOPOLISTIC MARKET EQUILIBRIUM
p
QDQS100
p1 =$500
p2 =$490
1 2
p3 =$475
3
pe
Discriminatory monopolistcharges the competitive marketprice to the last renter andrents the competitive quantityof close apartments
107
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
WHICH MARKET OUTCOMES ARE DESIRABLE Which is better
Perfect competition Monopoly Discriminatory monopoly
108
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Vilfredo Pareto 1848-1923 A Pareto outcome allows no ldquowasted
welfarerdquo ie the only way one personrsquos welfare can be
improved is to lower another personrsquos welfare
109
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Jill has an apartment Jack does not Jill values the apartment at $200 Jack would pay
$400 for it Jill could sublet the apartment to Jack for $300 Both gain so it was Pareto inefficient for Jill to
have the apartment
110
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY A Pareto inefficient outcome means there
remain unrealized mutual gains-to-trade Any market outcome that achieves all
possible gains-to-trade must be Pareto efficient
111
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Competitive equilibrium
all close apartment renters value them at the market price pe or more
all others value close apartments at less than pe
so no mutually beneficial trades remain so the outcome is Pareto efficient
112
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Discriminatory Monopoly
assignment of apartments is the same as with the perfectly competitive market
so the discriminatory monopoly outcome is also Pareto efficient
113
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Monopoly
not all apartments are occupied so a distant apartment renter could be assigned
a close apartment and have higher welfare without lowering anybody elsersquos welfare
so the monopoly outcome is Pareto inefficient
114
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
PARETO EFFICIENCY Rent Control
some close apartments are assigned to renters valuing them at below the competitive price pe
some renters valuing a close apartment above pe donrsquot get close apartments
Pareto inefficient outcome
115
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
Market StructurePerfect
CompetitionPure
Monopoly
Monopolistic Competition Oligopoly Duopoly Monopoly
The further right on the scale the greater the degree of monopoly power exercised by the firm
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET STRUCTURECharacteristics Look at these everyday products ndash what type of market structure are the producers of these products operating in
Canon SLR Camera Bananas
Mercedes CLK Coupe
Vodka
Electric Guitar ndash Jazz Body
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
世界之巔急先鋒 雪巴人
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業
MARKET STRUCTURE amp POLICY
藥物市場媒體市場 電子業