LOM Issues: Classification

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LOM Issues Classification
Brendon Towle IEEE LOM WG Meeting, Sept 21,
2000 Sedona, AZ, USA
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Brief Outline

• General Issues
• Example of a problem
• A Proposal
• Philosophical Issues

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Classification Issues

• The classification structure forms a language
  for expressing characteristics of LOs
• This language, unfortunately, is not very
  expressive

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Example Representing Media

• We need large amounts of information about media
  in LOs
• Media type (movie, text, etc)
• Media purpose (aesthetics, character development,
  navigation, etc)
• Additional info for specific purposes
• If purpose is character development, age, gender,
  etc of character

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Representing Media in Classification

• For each media element in LO, have one
  Classification record with purpose Media
• Each Classification record has one TaxonPath for
  each characteristic
• Each TaxonPath has a source which identifies the
  characteristic

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Problems with that solution

• Seems to abuse notion of purpose
• Its not the purpose of the classification, its
  the part of the LO that is classified
• Requires duplication to get multiple TaxonPaths
  for one source (necessary because source really
  means characteristic in our use)
• Semantics of duplication unclear

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Proposal

• Allow Taxons to nest
• Taxonomic stairways would be represented by
  singly nested taxons
• Tree structures would be represented by multiply
  nested taxons
• Sets of attributes would be represented by
  multiple taxons (nested or not)
• Allowing the use of ID and IDREF attributes would
  allow webs as well

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Example (in XML)
ltClassificationgt ltPurposegtLearningResourceTypelt/
Purposegt ltTaxonPathgt ltSourcegtKPLearningResou
rceTypelt/Sourcegt ltTaxongt
ltEntrygtConceptlt/Entrygt lt/Taxongt ltTaxongt
ltEntrygtProblemlt/Entrygt ltTaxongt
ltEntrygtSolutionGenerationlt/Entrygt lt/Taxongt
lt/Taxongt lt/TaxonPathgt lt/Classificationgt
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Proposal, part 2

• Add an Aspect to categorization
• One of Aspect, Purpose would be required both
  would be allowed
• Allows schemes to state what part of the LO is
  being classified
• These two things, taken in concert, allow
  implementations to fully define new data elements
  in LOMwhich is the whole point!

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Philosophical Issues

• What is the purpose of Classification?
• General extension mechanism?
• Taxonomies only? (e.g., rocate within LoCSH)
• What are the semantics of
• Multiple classifications with same purpose?
• Multiple TaxonPaths with same source?