Discussion Class 1

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Discussion Class 1

• Three Information Retrieval Systems

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Discussion Classes
Format Questions. Ask a member of the class to
answer. Provide opportunity for others to
comment. When answering Stand up. Give your
name. Make sure that the TA hears it. Speak
clearly so that all the class can
hear. Suggestions Do not be shy at presenting
partial answers. Differing viewpoints are
welcome.
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Question 1 Document sets

• Each of the three information retrieval systems
  indexes a set
• of documents
• (a) What documents does Google index?
• What documents does the Library of Congress
  catalog index?
• What documents does Medline index?
• In each case are you searching surrogates or the
  full text of
• documents?

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Question 2 Palestine

• What in history led to the current turmoil in
  Palestine and
• the neighboring countries?
• How does the Library of Congress Catalog help a
  user answer this question?
• (b) How does Google help a user answer this
  question?
• Under what circumstance would you use each system
  to find
• information such as this?

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Question 3 Fielded searching

• For each of the search systems
• (a) Is it full text or fielded searching?
• What fields can you search on?
• How was the fielded information created (by
  author, by
• professional cataloger/indexer, by algorithm,
  etc.)?

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Question 4 Language support
Which of the following does each system support?
(a) stop lists (ignore common words) (b)
stemming (compute, computer and computing) (c)
thesaurus (heart attack, cardiac arrest) (d)
other (e.g., gazetteer)
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Question 5 Search options

• What Boolean operators does each system offer
  (and, or, not, etc.)?
• (b) What special symbols does each system allow
  in queries as wild cards, etc. (e.g., ? as a
  truncation symbol)?
• (c) What is meant by a "search limit"?

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Question 6 Browsing

• (a) What support does Google give for browsing?
• What support does the Library of Congress Catalog
  give for browsing?
• What support does Medline give for browsing?

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Question 7 Red wine

• What is the medical evidence that red wine is
  good
• or bad for your health?
• (a) How does Google help a user answer this
  question?
• How does Medline help a user answer this
  question?
• Under what circumstance would you use each system
  
• to find information such as this?