METADATA AND SUBJECT ANALYSIS Lois Mai Chan School of Library and Information Science University of

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METADATA AND SUBJECT ANALYSISLois Mai
ChanSchool of Library and Information
ScienceUniversity of Kentucky
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Charge to the Subcommittee on Metadata and
Subject Analysis

• "Identify and study the major issues surrounding
  the use of metadata in the subject analysis and
  classification of digital resources. Provide
  discussion forums and programs relevant to these
  issues."

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Subject Analysis of Web Resources

• To control or not to control the vocabulary?
• Options
• (1) Keywords (free-text) only
• (2) Keywords and Controlled vocabulary
• (3) Controlled vocabulary only

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Keywords (free-text) only

• (1) Lack of synonym control
• (2) Lack of homograph control
• (3) Lack of indication of term relationships

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Controlled vocabulary

• (1) Existing schemes
• Are existing schemes suitable for use on the
  web?
• (2) Adaptation/modification of existing systems
• What needs to be modified, and how?
• Who will be responsible?
• (3) New scheme(s)
• Who will develop and maintain it/them?

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Controlled vocabulary

• (4) A single controlled vocabulary - "one size
  fits all
• Which one?
• (5) General vs. specialized schemes
• (6) Multiple vocabularies
• How do we harmonize terms from different
  vocabularies?
• (7) Metathesaurus
• cf. Unified Medical Language System
  (UMLS)

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Controlled Vocabulary - Structural Issues

• 1. Semantics
• Term specificity
• Synonyms and homographs
• Term relationships
• 2. Syntax Full strings
• Single-concept descriptors

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Controlled Vocabulary - Application Issues

• 1. Consistency
• 2. Summarization vs. exhaustive indexing
• 3. Placement of non-topical data
• 4. Pre-coordination vs. post-coordination

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Possible Strategies for Implementing Controlled
Vocabulary

• Define the functional requirements of subject
  data in the metadata record
• Consider the desirability and feasibility of
  creating a new controlled vocabulary
• Examine and determine the suitability of existing
  controlled vocabularies (e.g., LCSH) for use in
  metadata records

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Functional Requirements

• Schemes for supplying subject data in the
  metadata record should
• be simple and easy to apply and to comprehend
• be intuitive so that sophisticated training in
  subject indexing and classification, while highly
  desirable, is not required in order to implement
  them

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Functional Requirements

• be scalable for implementation from the simplest
  to the most sophisticated
• be logical so that it requires the least effort
  to understand and to implement

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Functional Requirements

• be appropriate to the specific discipline and
  subject, and to the domain of implementation such
  as libraries, museums, archives, information
  services, the scientific community, and personal
  knowledge management and,
• be interoperable across disciplines and in
  various knowledge discovery and access
  environments, not the least among which is the
  OPAC

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Role of LCSH

• LCSH in the OPAC
• Role of LCSH LCSH in the Web Environment
• Advantages
• Limitations

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Requirements for Implementing LCSH Effectively

• (1) trained catalogers
• (2) systems with index browsing capability
• (3) systems with online thesaurus display
• Unfortunately, they are all in short supply in
  the web environment

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LCSH in the Metadata Record

• Issues to be considered
• Semantics Terminology and term
  relationships
• Syntax How words are put together to form
  subject terms

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Possible Approaches

• Separating syntax from semantics
• Designing a series of flexible syntax
• Pre-coordination vs. post-coordination

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Syntax Issues -

• Pre-coordination
• Post-coordination

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Accommodating Multiple Subject Vocabularies

• Harmonization of subject terms from different
  controlled vocabularies
• Feasibility of developing a general metathesaurus
  or expanding the medical metathesaurus to include
  indexing terms covering all subject areas

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Possible Strategies for Implementing Controlled
Vocabulary - Design Issues

• Provide online authority control or display of
  controlled vocabulary terms
• Design interfaces that enable assigning subject
  terms by "clicking and dragging" from a subject
  term list and linking author-input terms to
  controlled vocabulary

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Overriding Principles (cf. Dublin Core)

• The Subcommittee endorses the overriding
  principles articulated in the Dublin Core
• Simplicity
• To allow the creation of metadata records by
  persons not necessarily trained in sophisticated
  methods of bibliographic control (cf. Dublin
  Core)
• Semantic interoperability
• Flexibility