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Web Searching and PPT

Web Searching and PPT. Searching for Information on the Web. Goals: Decrease number of search results Increase number of relevant results Method: Structured vs keyword searching Use any of several search tips and commands

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Web Searching and PPT

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  1. Web Searching and PPT

  2. Searching for Information on the Web • Goals: • Decrease number of search results • Increase number of relevant results • Method: Structured vs keyword searching • Use any of several search tips and commands • Search engines vary in terms of the commands they support. Just because one does not find it does not mean its not there.

  3. Different search engines are different. All have “help” • http://www.google.com/intl/en/help/basics.html • http://search.yahoo.com/web/advanced • http://help.ask.com/en/docs/about/adv_search_tips.shtml • http://www.dogpile.com/info.dogpl/search/help/faq.htm?r_fcid=416&r_fcp=top

  4. Search Command Options • “Search engine math” • Basic tips to improve your search • Field searching • Search for terms within specific parts of the document (e.g., title) • Boolean and other advanced commands (e.g., AND, OR) • Search assistance and display features • Features of the engines, themselves

  5. Search Engine Math • Include term (+) • To ensure word is included in search e.g., +camping +Arkansas • Exclude term (-) • find pages that have one word on them, but not another word e.g., +apples -computer • Phrase (“_”) e.g., “social psychology”

  6. Search Engine Math II • Match any term • Automatic in some, option on others • Match all terms • Use + or menu; automatic at some (google) • Truncation/Wildcard (*) • To find all forms of a word • archaeolog* (-y, -ical, -ist) • Stemming: finds all forms based on the stem automatically • Automatic at google

  7. Field Searching and Limiting • Title search -- to search for words w/in titles of web pages e.g., +title:elephant +species • Site search -- to search w/in documents on a specific site e.g., domain:memphis.edu psychology • URL search -- to search within the text of URLs e.g., url:memphis.edu

  8. Field Searching and Limiting II • Link search -- to search for pages that link to a particular page or domain e.g., link:psyc.memphis.edu/students/../ • Limit by language • Search for documents in a particular language • Limit by date pages were created or modified • Limit by type • Engineering filetype:ppt

  9. Boolean Commands • AND returns pages containing all search terms joined by AND e.g., Mars AND planet AND life • OR returns pages containing any or all search terms joined by OR e.g., “bed and breakfast” or inn • NOT returns pages containing the first but not the second term e.g., clinton NOT lewinsky

  10. Boolean Commands II • NEAR returns pages containing keywords near each other on the page e.g., psychology NEAR history (distance can be specified . Alta Vista does this) • Nesting Boolean commands provides for complex queries e.g., psychology AND (social OR cognitive) . . . If no parentheses . . . (psychology AND social) OR cognitive

  11. Combining Commands • Examples: • (cat* OR feline*) AND “endangered species” • +title:psychology +dream* -Freud* • “star trek” -voyager -“deep space nine” -“next generation” • Works only if search engine supports each command, obviously

  12. Search Assistance Features • Related Searches • Search engine provides related searches after a search is complete • Find Similar • Provides ability to find other pages that seem similar to those you like • Search Within • Do a second search within results already generated

  13. Display Features • Ability to sort results by date (created or modified), with most recent documents listed first • Some search engines display the date page was created or modified * Note: dates can be unreliable (gotten from server) • Ability to increase the number of results that are displayed • Google use a patented algorithm for “search order” display.

  14. A Note about Meta-search Engines • Dogpile and MetaCrawler will allow many of these commands, but if the engine they are polling does not, you may end up with funky results • Sometimes, the syntax will be removed (e.g., Boolean operators) • At other times, however, they will become a keyword in the search (e.g., title:)

  15. Specialty Search Engines • Catalog information particular to a narrow topic area • Pro: potentially more coverage versus the general search services • Con: don’t provide you the search options and flexibility of general search engines • A directory of search engines (general and specialty): www.beaucoup.com

  16. Example • Compound interest quote

  17. Checking things. • Not everything on the web is “correct” • Not everything in print is “correct”. • Often have to “check your facts…” • http://timpanogos.wordpress.com/2006/07/22/einstein-compound-interest-does-not-compute/

  18. Sources • Understand the “trustworthiness” of the source. • Credible publishers (webster) Probably okay • Wikipedia reasonable but less reliable (many can fix, but still many add/change). • Blogs: often dubious • Ask why its there, what is their interest.

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