DIALOG 2: Controlled Vocabulary

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DIALOG 2Controlled Vocabulary
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why CV is a good idea

• linguistic issues form v. meaning
• 1 concept can have multiple forms (synonymy)
• teachers/instructors/educators/etc
• blood levels/serum levels/blood concentration
• Clemens, Samuel/Twain, Mark
• 1 term can have multiple meanings (ambiguity,
  polysemy)
• mercury (car, mythology, metal, planet)
• John Smith (poet, economist, fake name)

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control

• provides for consistent representation of subject
  matter, avoids dispersion at indexing or
  searching
• facilitates broad searching by bringing together
  terms that are related, both paradigmatically
  (BT/NT) and syntagmatically (RT)
• facilitates gathering, comprehensiveness
• can be dated, nonintuitive, insufficiently
  specific, expensive
• 2 primary kinds subject, name authority

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controlled vocabulary searching

• often a good idea
• intellectual control
• eases access, provides precision
• removes ambiguity (CRACK, BUSH, CHINA)
• can broaden understanding of a topic
• not the answer but often a good start

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suffix searching

• 2 very closely related kinds limits and
  qualifiers
• limits used for year, language, other special
  features of documents
• /ENG, /2002, /HUMAN
• these are tags in records, not necessarily fields
  of their own (could also be fields such as
  language, year), so searching is whether or not
  that tag is present, limiting results to those
  where it is

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qualifiers

• qualify a search term or string to a particular
  field
• a precision tool
• an unqualified search goes to all Basic Index
  fields
• a qualified search is specified
• S COMPUTER?/TI
• S FROG/TI,AB
• S S2/TI post-qualification

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controlled vocabularytechnique

• search phrase descriptors as phrases
• S TEST VALIDITY
• include parentheticals if needed
• S BANDS (MUSIC)

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controlled vocabularytechnique

• search single-word descriptors depending on
  results you want
• anywhere leave it alone
• in descriptors /DE
• as the descriptor /DF
• as major descriptor /MAJ (if available)
• ORed with narrower terms Explode (if available)
  !