LIR 10 Week 7

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LIR 10 Week 7

• Boolean Searching and Online Periodical Databases

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LIR 10 search methods so far

• Youve searched the OPAC for Library of Congress
  subject headings to find books on your topic.
• Youve browsed through periodical indexes for
  subject headings and subheadings.
• Youve searched reference books for information
  about your topic in the books index or for
  alphabetical entries in the main body of the
  book.
• Now youre ready to create your own searches
  using Boolean logic!

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Constructing Searches with Boolean Logic

• Boolean logic is the term used to describe the
  logical relationship among search terms.
  Boolean refers to the 19th century Irish
  mathematician George Boole.
• Boolean logic consists of three logical
  operators
• OR
• AND
• NOT

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OR

• OR widens a search by instructing the computer to
  look for every record that includes any of the
  search terms specified in the statement.
• The OR operator is most commonly used when there
  are synonyms for a search concept that should be
  considered.
• For example, let's say you are interested in
  conducting a search for information about the
  theater. You might enter the search statement
  theater OR drama OR performance

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OR

• The Venn diagram below illustrates the search.

• This search instructs the database or search
  engine to give you all the articles that include
  the word theater or
• all the articles that include the word drama or
• all the articles that include the word
  performance or
• all the articles that include any one term, or
  both, or all three.

theater OR drama OR performance
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OR

• The more terms combined in a search using OR
  logic, the more records will be retrieved

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AND

• Use AND to narrow your search. Using AND
  instructs the database or search engine to
  retrieve only the records that contain all the
  search terms that you have specified in your
  statement.
• For example, if you are interested specifically
  in improvisational theater, you would enter the
  search
• improvisational AND theater
• Your recall (search results) should include
  articles with both the words improvisational and
  theater, in any order. If an article contains
  only the word improvisational, or if it only
  contains the word theater, it won't appear in
  your search results.

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AND

• The Venn diagram below illustrates the search.

• This search instructs the database or search
  engine to give you all the articles that include
  the words improvisational and theater.
• The grey section represents the intersection of
  the two terms. All search results come from that
  intersection.
• Articles that include the word improvisational
  without the word theater, and vice versa, will
  not be included.

improvisational AND theater
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AND

• The more you use AND, the narrower your search
  results will become.

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NOT

• The NOT operator allows you to exclude records
  with certain words from your search. Word order
  is very important when using the NOT operator in
  a statement. For example
• theater NOT improvisational
• will return all the records that contain the word
  theater except the ones that also contain the
  word improvisational.

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NOT

• The Venn diagram below illustrates the search.

• This search instructs the database or search
  engine to give you all the articles that include
  the word theater but do not include the word
  improvisational.
• The grey section represents the records that
  would be returned by the search.
• Articles that include the word theater that also
  include the word improvisational would not be
  included.

theater NOT improvisational
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NOT

• Using NOT can be tricky. It is possible to
  exclude documents that may in fact be relevant.

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Summary

• OR retrieves the largest amount of search
  results. Any and all terms included will be
  retrieved.
• AND narrows the search results to the
  intersection of the terms.
• NOT narrows the search by excluding the search
  term specified.

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Precision vs. Recall

• PRECISION equals the number of articles that are
  directly related to a topic that you retrieve as
  a result of your search.
• RECALL equals the total number of articles that
  are peripherally related to the topic that you
  retrieve as a result of your search.

• When you narrow your search, you hope to increase
  your precision.
• When you broaden your search, you hope to
  increase your recall.

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Precision vs. Recall

• The research process involves adjusting these
  factors until you get the precise information you
  need to answer your question, and until you
  retrieve a sufficient amount of information about
  it to support your paper.

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Online Periodical Resources

• Access SRJC databases on campus or from home
• http//www.santarosa.edu/library/ftdb
• Apply for a PIN
• Start searching!

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Subscription Databases vs. Internet Search
Engines

• Subscription databases contain citations and
  entire articles (usually called full text).
• Thousands of magazines, newspapers and other
  documents are represented in each database.

• Internet search engines will search for web
  pages, images, PDF documents and other files
  available on the Internet.
• Search engines offer limited precision.

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Different Databases for Different Needs

• Aggregators or Vendors companies that provide
  databases.
• The same aggregator or vendor may have different
  versions of its databases that it markets to
  different types of institutions or organizations
  (Old Navy vs. Prada model).
• For example, the ProQuest Newspaper database you
  search on the public librarys web page will
  contain different content than the ProQuest
  Newspaper database you search at SRJC.

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The Right Database for the Right Information Need

• General vs. Subject-specific
• Look at the Database Description (the round i
  icon next to the database name)
• Check the date range, periodicals covered and
  help screen
• After selecting a database, look at the opening
  screen take a minute to see where you are in
  the database

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Databases for Week 7

• ProQuest Magazines and Newspapers
• Articles from thousands of popular magazines and
  newspapers, as well as scholarly journals, news
  services and other information sources.
• Covers over 560 U.S. world newspapers.
• Covers over 2,500 magazines and journals.

• Expanded Academic ASAP
• Full text of articles in over 2,150 magazines and
  scholarly journals.
• Citations only for an additional 1,355 magazines
  and journals.
• Over 1,700 scholarly or "refereed" journals are
  included.

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Homework for next week

• Use either ProQuest or Expanded Academic ASAP.
• Use Boolean operators to find articles on your
  topic.
• Answer the questions on your worksheet.
• Print out the first page of the article you
  choose and include it with your worksheet.