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Alabama Library Association • April 25, 2012
Jackie Brodsky | Naomi Gold School of Library and Information Studies, University of Alabama
Brett Spencer | Sara Whitver Gorgas Library, University of Alabama
What is the “Deep Web?”
How does its content differ from the surface web?
Why should this interest us?
What are tools and methods for searching it?
What You’ll Learn
Term originated in three sources
Michael K. Bergman“The Deep Web: Surfacing Hidden Value.” Journal of Electronic Publishing Volume 7 (August 2001). Available electronically; see LibGuide for URL.
Chris Sherman and Gary PriceThe Invisible Web: Uncovering Sources Search Engines Can’t See Medford, NJ: CyberAge Books, 2001.
“The Invisible Web: Uncovering Sources Search Engines Can’t See.” Library Trends 52 (Fall 2003): 282-298. Available electronically; see LibGuide for URL.
What is the “Deep Web?”
Text Text Text
What You’re Missing
surface web—small percentage of
web-based content
____________
What you’re missing
According to some estimates, 4000-5000 times larger than
the surface web.
Dynamic state of the web means that rate of growth
defies quantification.
Dynamic Content- Not crawled by spiders / search engines- Can be recognized from the structure of the URL, e.g. containing cfm, cgi, php
Material residing in databases—pages in non-HTML format- Search engines can locate the titles of databases, but can’t index specific contents.
Subject to Search engine/website limitations- Sites too large to be indexed completely- Site owner does not allow indexing- Information changes rapidly
What is the “Deep Web?”
Text Text Text
Why is it Important?
Resources on invisible/ deep web usually of higher quality than those on surface web.
Why?
— Written or validated by authorities
— Focused, specialized materials created for scholarly, professional, or expert use
Resources on invisible web usually of higher quality than those on surface web.
Text Text Text
Why do we need it?
— Supplement subscription databases
— Meet needs of a variety of patrons with high-quality, web-based resources
— Assist patrons to learn how to search the web more skillfully
Finding Deep Web Sources—Tools
Complete Planet—The Deep Web Directory. A product of the site Bright Planet.
Infomine—Scholarly Internet Resource Directory
Product of several U.S. libraries. Mines information from databases, electronic journals, electronic books, bulletin boards, mailing lists, online library card catalogs, articles, directories of researchers, and many other resources.
Finding Deep Web Sources—Searching Directly
Three Step Search Process for Finding Deep Web Materials
1. Type in broad subject area, e.g. “history”
2. Type in type of information being sought: documents, images, statistics
3. Type in a deep web designator e.g. “database,” “search engine,” “archive”
ExampleArchitecture—Images—Database
Finding Deep Web Sources—Searching Directly
Use term “database” in an ordinary Google search: corn + Alabama + database produces . . .
Environmental Working Group 2011 Farm Subsidy Database
Ambiguity
Difficult to predict what sites will or won't be found on the Deep Web.
Sites replicate some content in static pages—hybrid of visible and invisible?
Sites replicate all content in static pages—visible in search engines given well-formed search?
Sites replicate none of their content in static pages and must be searched using Deep Web-specific methods—totally invisible?
Search engines can change their policies on what they exclude and include.
Search Demonstrations
Deep Web Search Demonstrations:Brett Spencer
Librarians Information about accessibility tools
Users researching disabilities Databases about disabilities
Persons with disabilities accessing resources
Accessible databases
Accessibility Issues
Sample Database of Accessibility Tools
Sample Databasesabout Disabilities
Selection of Accessibility Tools
PC— Built-in Narrator Magnifier On-screen keyboard
Third party JAWS—narration and output to Braille reader
MAC VoiceOver Zoom Display—change to white-on-black and change contrast
Accessibility of Databases
Color / ContrastContrast Headings / Hyperlinks Information available in
alternative formats
Descriptions of images
Transcripts or captions for video/audio
Accessible Databases
Partially Accessible Database
Partially Accessible Database
Collection Development:Organizing Your Sources
• Do you wait until you’re in the middle of a reference interview to do your collection development?
• When you’re finished with a source, do you walk away and forget about it as if it never existed?
Keeping Track
• DeliciousDelicious
• DiigoDiigo
• LibGuidesLibGuides
• WikiWiki
Keep track of your discoveries so you can find them again!
Folksonomy
Learn More
http://bama-slis.libguides.com/deepweb
Contact us:Jackie Brodsky [email protected] Gold [email protected] Spencer [email protected] Whitver [email protected]
