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Basics

Basics. Computer Internet Search Strategy. Computer Basics. IP address: Internet Protocol Address An identifier for a computer or device on a network The format of an IP address is four numbers separated by periods. Each number can be zero to 255. For example, 134.140.112.9

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Basics

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  1. Basics Computer Internet Search Strategy

  2. Computer Basics • IP address: Internet Protocol Address • An identifier for a computer or device on a network • The format of an IP address is four numbers separated by periods. Each number can be zero to 255. For example, 134.140.112.9 • Can be static or on the fly

  3. Internet Basics • The Internet vs. The World Wide Web • The Internet is not synonymous with World Wide Web

  4. Internet Basics • The Internet is a network of computer networks • Computers connected so they can communicate with any other computer also connected, or networked, to the internet • Used for communicating many kinds of information using protocols including SMTP for email and HTTP for web pages • The World Wide Web is only one part of the Internet, which also includes email, newsgroups, and instant messaging

  5. Internet Basics • The World Wide Web is a “web” of documents, called web pages, connected via hyperlinks • One way of communicating on the internet • Uses HTTP protocol • Accessed via browsers, such as Internet Explorer or Netscape • Web pages can include graphics, audio, text, and video.

  6. Internet Basics • Web pages vs. websites • A web page is a document on the World Wide Web • A website is a collection of web pages including a home page, the main page on the site and first to be viewed, plus additional, related, hyperlinked pages

  7. Internet Basics • URL: Uniform Resource Locator • The unique address of a web page • Can be persistent or dynamic • Format: http://web.simmons.edu/~krajewsk

  8. Internet Basics • A hyperlink is an element in an web page that links to another place in the same page or to an entirely different web page • Click on the hyperlink to access the linked web page

  9. Internet Basics • A domain is a group of computers sharing a part of an IP address • Consist of a range of IP addresses • Will share the same basis of url • www.simmons.edu/libraries and www.simmons.edu/gslis are all part of the simmons.edu domain

  10. Cache • Copies of frequently used data stored on a local hard drive • Allows information to be accessed more quickly because it does not have to be retrieved from the internet each time it is called

  11. Browser • A Web browser isa software application used to locate and display Web pages. • Mostbrowserscan display text, graphics, audio, and video

  12. Internet Basics • On the web vs. Access via the web • On the web: online, free, available to everyone • Via the web: online, but in a special, restricted database, requiring a login and /or subscription fee

  13. Internet Basics • A search engine is a program that searches the web for specified keywords and returns a list of the web pages where the keywords were found

  14. Search Basics • Searching is the process of querying a database—a library catalog, periodical index, or search engine—to find relevant information

  15. Search Basics • Each item in a database is called a RECORD • All records are INDEXED by specialists or computers who pull out key pieces of information • Each key piece of information indexed belongs in a specific FIELD, which is generally searchable (author, title, or specific to subject) • HITS are the number of records in the entire database that match your search terms

  16. Search Basics • Syntax – The “language” of the database you are searching • HOW you translate you information need into a query

  17. Search Basics Boolean operators are connectors used to define the relationship between or among your search terms: • OR – EitherTerm AorTerm B must be present on a web page for it to be included in your results list • AND – BothTerm AandTerm B must be present for the web page to appear on the results list • NOT – Term Amust be present and Term Bmust not be present for the web page to appear on the results list

  18. Dogs OR Cats • Gets both, might be overlap Dogs Cats

  19. Dogs AND Cats • Only gets records where both appear Dogs Cats

  20. Dogs NOT Cats • Eliminates Records where Cats Appear Dogs Cats

  21. Parentheses: Nesting (Dog? or Pupp?) and (Cat? or Kitten?) Dog or Dogs or Puppy or Puppies Cat or Cats or Kitten or Kittens

  22. Search Basics Proximity operators specify how close search terms must appear together in a web page to be included in the results list: • Next to – Term A and Term B must appear right next to each other for the web page to appear in the results list • Near – Term A and Term B must be near each other for the web page to appear in the results list • Within # - Term A and Term B must appear within a certain number of words for the web page to appear in the results list • Same paragraph - Term A and Term B must appear in the same paragraph for the web page to appear in the results list

  23. Search Basics • Truncation is the use of a symbol to stand for any possible ending of a root • Eliminates the need for long searches with similar words separated by the Boolean operator OR • Example Child* The asterisk * can stand for any possible ending of the root child, such as child, children, childhood, child’s, children’s,

  24. Search Basics • Wildcard symbols can stand for any character or characters within a word • Useful for roots that have many unrelated endings • Example wom?n can stand for woman, women, womon, womyn

  25. Search Basics • Searching terms as a phrase dictates that they appear in the order specified, right next to each other, in the web page • Sometimes automatic • Useful in searching for short quotations • Example “hot cross bun” finds only web pages with that exact phrase, eliminating those that have the words hot, cross, and bun unrelated to one another

  26. Search Basics • Limits restrict what part of the web page is searched • Limited limiting capabilities with search engines • Usually searches metadata, information that cannot be seen on the web page, itself • Example Language:English finds only web pages with English language text

  27. Search Basics Search Index syntax varies • Usually no field searching • Limited truncation and wildcards • Boolean “AND” may be assumed • Phrase syntax important • Limit search effectiveness dependent on web page creators’ included metadata

  28. Search Basics • Natural language searching common with search engines • No connectors (no boolean, proximity, etc.) • Statistical algorithm for “relevance” • Term frequency • Term location • Proximity of terms to each other • Uniqueness of term • Possibly “popularity” of document • Build taxonomy “on the fly”

  29. Search Strategies Key Factors for Successful Web Searching : • Which search engines/resources you choose for the search • How carefully you formulate & execute the search terms & search logic • How much information is actually available

  30. Search Strategies • Precision & Recall are traditional measures of a successful search • Recall: % of relevant records found of all the relevant records (possible hits) in file • “How much of the good stuff did your search produce?” • measured against all the possible relevant hits • Precision: % of relevant records within search results • “How much of the bad stuff did your search produce?” • measured against what you actually retrieved

  31. Search Strategies Precision vs. Recall Usually inverse relationship High Recall Low Precision Low High

  32. Search Strategies • Precision is assured by choosing enough appropriate concepts • Recall is assured by choosing enough appropriate synonyms

  33. Search Strategies Choosing Search Words • Make a list of concrete words that define the topic • Identify alternatives

  34. Search Strategies Simplify words: • Plurals: s, es, y-ies often will automatically be searched • Truncate (often * or !): packag* or wrap*

  35. Search Strategies Eliminate general and assumed/applied terms • Leave out “science” if you are search a science search engine • Consider whether or not to search “efforts” - general term implied in most articles – an web page discussing effort to do something is likely not to include the word “efforts”

  36. Search Strategies Be the most specific (narrowest) when: • Sure of target document(s) • Don’t care about recall (precision first) • Don’t have time to plan • “Quick & Dirty”

  37. Search Strategies To narrow a search • “And” in a new concept • Use fewer terms in concept sets • Be more specific - use proximity over ands • Go from free text to controlled vocabulary/fields • Truncate further right • Use narrower, more specific vocabulary terms • Qualify search strategies to titles, abstracts, descriptors • Limit by language, publication year, type

  38. Search Strategies Be less specific (broadest) when: • Need comprehensive retrieval (high recall) • “Feeling your way” • Unsure of terms • Unsure of database content • Fuzzy topic

  39. Search Strategies To broaden a search: • Eliminate a concept set - the least crucial • OR in more terms • Be less specific - go from descriptors to free text • Use broader ands instead of proximity • Truncate further left • Use broader controlled vocabulary terms • Remove qualifiers; search full text • Remove limitations

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