PowerPoint Presentation - Web Search Tools

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"When they say, 'Gee it's an information
explosion!', no, it's not an explosion, it's a
disgorgement of the bowels is what it is. Every
idiotic thing that anybody could possibly write
or say or think can get into the body politic
now, where before things would have to have some
merit to go through the publishing routine, now,
ANYTHING." - Harlan Ellison
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Web Search Tools

• How to get the most out of search engines, web
  directories, and meta-searchers

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The Web is great for locating

• Current information
• Background information related to current events
• Live, as-it-happens information (e.g., breaking
  news stories)
• Customizable information (e.g., Yahoo add-ons)
• Specific facts
• Information buried within documents that you
  cant locate using an online catalog, printed or
  CD-ROM indexes, or tables of contents
• Multimedia resources pictures, sound clips,
  maps, etc.
• Government information
• Timely information stock quotes, real estate and
  job listings
• Information that you can subsequently keyword
  search using a search engine

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but it has only modest amounts of

• Books
• Archival materials (manuscripts, census data,
  historical documents, etc.)
• Scholarly criticism of literature, art, music,
  etc.
• Retrospective databases
• Citations or full-text for articles in older
  periodicals

The web is also not a reliable medium for
long-term storage and retrieval of information.
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The Invisible Web

• Sometimes called the Deep Web
• Information that search engines cannot or refuse
  to index because it is locked up within databases
• At least 500 times bigger than the part of the
  web visible to search engines
• Want to know more? Go to www.brightplanet.com
• The bottom line DONT RELY ON GENERAL WEB SEARCH
  TOOLS FOR ALL YOUR INFORMATION NEEDS!

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Web Indexes, Directories Review Sites

• Built by humans
• Selective
• Evaluated
• Organized according to a scheme
• Most like a Subject search on ALICE
• Based on a thesaurus (pre-defined list of terms)
• Includes see see also references

• Two types of searching browse and keyword
• Can use various search techniques to focus
  results
• Not a live search
• Major advantage user-friendly can be easily
  browsed
• Major disadvantage limited number of sites
  indexed

Cannot find information located inside other
databases, e.g., ALICE or Academic Search Premier.
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InfoTree
Ohio U. Librarian
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Web Search Engines

• Built by robot programs, not humans
• Not selective
• Not evaluated
• Results arranged but not organized
• Most like a keyword search on ALICE
• No thesaurus
• No cross-references

• Keyword searching only
• Must use keyword search techniques to focus
  results
• Not a live search
• Major advantage can locate information buried
  inside web pages
• Major disadvantage can bring back too many
  results

Cannot find information located inside other
databases, e.g., ALICE, Periodical Abstracts, etc.
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? Dogs 2 Documents ? Cats 2 Documents
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? Dogs OR Cats 3 Documents ? Dogs AND Cats 1
Document ? Dogs NOT Cats 1 Document
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Search Tools Arent Perfect
Search Tool of Web Indexed Outdated
Links
AltaVista 28
2.5
Excite 14
2.0
HotBot 34
5.3
Infoseek 10
2.5
Lycos 3
1.5
Northern Light 20
5.0
Based on a study done in December 1997 and
published in the April 3, 1998 issue of Science.
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and Theyre Losing Ground!
Search Tool of Web Indexed of Web
Indexed Dec. 1997
Feb. 1999
AltaVista Excite HotBot Infoseek Lycos Northern
Light Snap Google Yahoo
28.0 14.0 34.0 10.0 3.0 20.0
15.5 5.6 11.3 8.0 2.5 16.0 15.5 7.8 7.4
Based on a study done in December 1997 and
published in the April 3, 1998 issue of Science,
and a follow-up study done in February 1999 and
published in the July 8, 1999 issue of Nature.
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Search Engine Reliability
Searches done May 3, 1999 on AltaVista

• Search Terms
• mars
• mars jupiter
• mars jupiter mercury
• mars jupiter mercury pluto
• mars jupiter mercury pluto mickey

• Number of Hits
• 1,844,953
• 615,650
• 635,900
• 423,990
• 1,103,810

What is the default, AND or OR?
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Search Engine Reliability (cont.)

• The last search had, as its 5 result, a page
  titled Terry Pluto on Mickey Mantle and Jerry
  Garcia. None of the other planets showed up
  anywhere in the document.
• 8 of the other top 10 were about Disney
  characters, and the only one about planets was
  titled Tiny Pluto No Mickey Mouse Planet.

(from a librarian at Wesleyan U.)
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Meta-Search Tools

• Results gathered by sophisticated search programs
• Not selective
• Not evaluated
• Results arranged but not organized
• Most like an automated reference librarian
• No thesaurus
• No cross-references

• Keyword searching only search once multiple
  results (in simultaneous meta-searchers)
• Can use limited keyword search techniques
• Not a live search
• Major advantage saves time and keystrokes
• Major disadvantage cant customize each search

Cannot find information located inside other
databases, e.g., ALICE, Periodical Abstracts,
etc.
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Evaluating Websites

• Accuracy
• Authority
• Coverage
• Currency
• Objectivity

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Citing Websites

• More than one correct way
• APA, MLA, etc.
• See http//www.library.ohiou.edu/libinfo/howto/cit
  ing.htm
• Example (MLA)
• William Faulkner on the Web. 7 July 1999. NU of
  Mississippi. 20 Sept. 1999. http//www.mcsr.olemis
  s.edu/egjbp/faulkner/
• faulkner.html.

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Points to remember

• Its not all on the web!
• Remember the Invisible Web
• Directories vs. Search Engines
• Use Advanced Search features
• No search engine is perfect
• Evaluate, Evaluate, Evaluate!