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Statistics for IACS

Dominique Fasbender

Control and management of agricultural land in IACS workshop

Baveno, 23-25 May 2016

Outline

Motivations

Examples for the IACS

Conclusion

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Introduction quote...

“The best thing about being a statistician is

that you get to play in everyone else's backyard.”

John Tukey (Bell Labs, Princeton University)

Did you say Statistics ?

“The science that deals with the collection, classification, analysis,

and interpretation of numerical facts or data.”

A statistic is a function of the data only.

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Statistics as…

DATA

INFO

Planning and decision tool

Modeling tool

« Information extractor »

Important to keep in mind !

How were the data acquired ?

What is donewith the data ?

Correct statisticalanalysis

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Outline

Motivations

Examples for the IACS

Conclusion

GNSS and orthoimage validation

Article 38 (4) of Commission Implementing Reg. (EU) No 809/2014“A single value buffer tolerance shall be defined for all area measurements performed using GNSS and/or orthoimagery. For this purpose the measurement tools used shall be validated for at least one validation class of buffer tolerance below the single value. However, the single tolerance value shall not exceed 1.25 m.”

ISO 5725-2

Decision

Plannification

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Sampling for LPIS QA Total: 123 images + 10 bonus

More than 44k RP’s inspected

ISO 2859/2-1985

Sampling for OTSC

Costs ?

Bias ?

CwRS and/or classical ?

“Cascade” sampling ?

1st and 2nd pillar ?

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Error rates after OTSCHow to analyze/interpret the error rates ?

Is there a difference between:

≈ opinion poll

≈ LPIS QA QE1b±

Margins of error ?

Full population ?

Zones ?

Random vs Risk ?

CwRS vs Classical ?

Analyses on LPIS population data

Looking at the samereference parcel over consecutive years- 6 years of data- 75M RPs/year

UNCHANGED MOVED

CHANGED AREA

DISAPPEARED

APPEARED

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Why such analyses ?

Intensity of activity ?Cleaning prior to LPIS QA ?

(before 2015)

Patterns ?

1000

m

Bad practices ?

3 cases of activity observed so far…

2010-2011

2011-2012

2012-2013

2010-2011

2011-2012

2012-2013

2010-2011

2011-2012

2012-2013

Could beenough… (?)

Reference ?Clear update cycle 0% 100% of RP that changed

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Reminder…

“The best thing about being a statistician is

that you get to play in everyone else's backyard.”

John Tukey (Bell Labs, Princeton University)

Outline

Motivations

Examples for the IACS

Conclusion

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Conclusion

• Use your data !

• Rely on us ! Contact us…

• Exchange ideas/practices among you…

• … and data if possible !

• Plateform of exchange ?

May the Stats be with you !

Thank you for your attention !

Any questions now ?

or later…

dominique.fasbender@jrc.ec.europa.eu