This document provides an overview of how search engines work and tips for effective searching. It discusses directories, search engines, metasearch engines, search fundamentals like Boolean queries and search terminology. Popular search engines like Google, Yahoo and Bing are mentioned. Tips are provided for formulating queries when you get too many or too few results. The document also discusses evaluating the credibility and reliability of websites.

1. SEARCH ENGINE Live and Learn 2010 Aj. Supichaya Nuntapunt School of Information Technology Mae Fah Luang University

2. The Web Defined Software application that allows us to publish and browse hypertext documents Transported over Internet HTTP Browsers are multiprotocol URL = Web address

3. Introduction Directories, Search Engines, and Metasearch Engines Search Fundamentals Search Strategies How Does a Search Engine Work?

4. Directories, Search Engines, and Metasearch Engines Directories Popular Directories Search Engines Popular Search Engines Metasearch Engines Popular Metasearch Engines

6. Directories Hierarchical representation of hyperlinks Top level of general topics Sublevels of more specialized subtopics Easy to use Not necessary to know exactly what looking for

7. Popular Directories AOL NetFind CNET Search.com Excite Infoseek Looksmart Lycos Yahoo! Open Directory (dmoz.com)

8. Search Engines Computer program: Accepts a query Searches database Returns URLs Permits query revision Problem: many times search engine return too many URLs. You need to be specific! Query syntax

9. Popular Search Engines Google (85.35%), Yahoo(6.29%), Bing (3.27%) AOL, Ask, AltaVista, Excite, HotBot, Lycos, Fast search (alltheweb.com), DogPile As of December 2009 Ross Shannon: HTML Source http://www.yourhtmlsource.com

10. HitWise http://www.hitwise.com/us/datacenter/main/dashboard-10133.html

11. Ranks.nl - Compare Search Engines http://www.ranks.nl/tools/compare.html

12. Metasearch Engines Call other search engines Use single query More matches

13. Popular Metasearch Engines Metasearch Metacrawler

14. Search Fundamentals Search Terminology Pattern Matching Queries Boolean Queries Search Domain Search Subjects

15. Search Terminology Search tool Query Query syntax Query semantics Hit or Match Relevancy score

16. Pattern Matching Queries Enter keyword(s) Search engine returns URLs

17. In-line/On-line: Fundamentals of the Internet and the World Wide Web

18. Boolean Queries George Boole AND, OR, and NOT Examples: You want to search for bass (the fish not the musical term) Vacation in either London or Paris

19. Search Domain Web Newsgroups Specialized databases Library

20. Search Subjects Metaspy shows searches for metacrawler in realtime. Google Search History

21. Introduction – Choose a search engine User-friendly interface Documentation Database size Relevancy scores

22. Too Many Hits: Search Specialization Add keywords Add AND or NOT Capitalize proper nouns Use first 20 URLs

23. Too Few Hits: Search Generalization Eliminate keywords Remove AND or NOT Enlarge search domain General keywords

25. How Google works BEFORE you search: “Crawls” pages on the public web Copies text & images, builds database WHEN you search: Automatically ranks pages in your results Word occurrence and location on page Popularity - a link to a page is a vote for it ~ 200 factors in all!

26. Searching Google Think “full text” = be specific war of 1812 economic causes vs. history Use academic & professional terms domestic architecture vs. houses genome society gets International Mammalian Genome Society also try combinations with association , research center , institute , directory , database

27. Searching Google Specify exact phrases “ tom bates” “what you're looking for is already inside you” Exclude or require a word proliferation -nuclear bush legacy +environment

28. Limit your search to … Web page title intitle:hybrid allintitle:hybrid mileage Website or domain site:whitehouse.gov “global warming” site:edu “global warming” File type filetype:ppt site:edu “global warming”

29. On the results page Search box (use to modify) “ Cache” “ Related pages” “ Translate this page”

30. Let’s try it ! Search Google Use our examples or your own topics www.google.com

31. Google’s other databases

32. Why go beyond Google? Search more of the web Yahoo! Get more options Exalead

33. Let’s try it ! Try other search tools Compare results with Google

34. CRITICAL EVALUATION Why Evaluate What You Find on the Web? Anyone can put up a web page Many pages not updated No quality control most sites not “peer-reviewed” less trustworthy than scholarly publications

35. Before you click to view the page... Look at the URL - personal page or site ? ~ or % or users or members Domain name appropriate for the content ? Restricted: edu, gov, mil, a few country codes (ca) Unrestricted: com, org, net, most country codes (us, uk) Published by an entity that makes sense ? News from its source? www. nytimes .com Advice from valid agency? www. mfu .ac.th e-learning . mfu .ac.th

36. Scan the perimeter of the page Can you tell who wrote it ? name of page author organization, institution, agency you recognize Credentials for the subject matter ? Look for links to: “ About us” “Philosophy” “Background” “Biography” Is it current enough ? Look for “last updated” date

37. Examine the content Text possibly forged ? Sources documented with links or notes ? do the links work ? Evidence of bias in text or sources ?

38. Do some detective work Search the URL in alexa.com Click on “Site info for … ” Who owns the domain? Who links to the site? What did the site look like in the past? www.archive.org/web/web.php (Wayback Machine)

39. Does it all add up ? Was the page put on the web to inform ? persuade ? sell ? as a parody or satire ? Is it appropriate for your purpose?

40. Try evaluating some sites... Search a topic in Google … Scan the first two pages of results Visit one or two sites evaluate their quality and reliability

41. Questions?

42. References John Kupersmith: University of California, Berkeley Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web THANK YOU