Subject Access and Thesaurus Developments

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Subject Access and Thesaurus Developments

• IM Forum May 9, 2001
• Nancy Brodie
• IM Division CIOB TBS
• Fay Hjartarson
• IRM NLC

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Organizing information to meet user needs
Portal
Taxonomy
Organizational information ecology
User community of discourse
A taxonomy allows portal managers to establish
categories of information and standardize
terminology
by recognizing differences in language
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What is taxonomy?

• A method of categorizing information using
  controlled and normalized vocabulary
• A taxonomy allows portal managers to
• Establish categories of information
• Standardize terminology
• User Term Normalized Term Government Terms
• Clean air Air Air quality
• Pollution
• Smog

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Examples of cluster taxonomy

• Cluster names and scope
• Cluster topics
• Canadian Health Network topics - 27
• Sources of Financing - 8 topics
• Statistics Canada themes
• Controlled subject terms - from a list or
  thesaurus
• Core GoC Subject Thesaurus
• http//dsp-psd.pwgsc.gc.ca/Thesaurus/index-e.html
• Statistics Canada Thesaurus
• Keywords with descriptors
• Consumer Gateway

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Elements of cluster taxonomy

• Cluster names and scope
• 35 clusters - scopes under development
• Cluster topics
• Controlled subject terms - from a list or
  thesaurus
• Keywords - uncontrolled or less controlled

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What is a thesaurus?

• A hierarchical list of controlled terms that is
  used both by indexers to describe information
  resources and by users to gain access to them.
• Provides synonyms and related terms to help the
  user identify the appropriate term within their
  scope of interest.
• Standardizes the external form and the meaning of
  index terms, thus ensuring that a particular
  concept or subject will always be represented in
  the same way in the index.

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Standards for thesaurus development

• ISO standards
• Guidelines for the establishment and development
  of monolingual thesauri (ISO 2788-1986)
• Guidelines for the establishment and development
  of multilingual thesauri (ISO 5964-1985)

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GoC Core Subject Thesaurus

• Recommended as the default thesaurus for use with
  CLF standard element Controlled Subject
• Meets ISO standards
• Represents all fields of knowledge
• Because of its exceptionally wide coverage, the
  subject descriptors are fairly general in nature.
  
• http//dsp-psd.pwgsc.gc.ca/Thesaurus/index-e.html

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GoC Core Subject Thesaurus

• Endorsed by the National Library of Canada
• Well constructed
• Needs to be kept up-to-date

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GoC Core Subject Thesaurus
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Sample Search Result
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Next Steps.

• Promote use of the GoC Core Subject Thesaurus
  where an existing controlled subject list is not
  in place
• Update list of thesauri currently in use
• Develop action plan for integration of thesauri
• Maintain the existing thesauri up-to-date

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Metadata for customization personalization

• Customization according to a user profile- not
  under the users control
• Personalization users subscribe, select
  categories - under users control
• Both require metadata i.e. tagging information
  according to
• audience or other demographic attributes
• geographic area
• industry sector
• Metadata elements and values must be standardized