RE: skos:TopConcept

> From: Bernard Vatant [mailto:bernard.vatant@mondeca.com] 
> Sent: Thursday, May 13, 2004 12:47 PM
> Subject: skos:TopConcept
> 
> skos:TopConcept is not defined as a subclass of skos:Concept
> 
> Why is it so? 

Because it's not a concept but a facet or category.  IMHO,
skos:Facet or skos:Category makes more sense than 
skos:TopConcept, due to the exact reason for your question.
What's being represented are facets for the arrangement of 
the concepts.  You can see this is MARC21-A.  You have the
subject headings, e.g. concepts, but the subject headings 
are arranged by specific categories.  These relate to the
1XX field ids, so you field id 100 is Personal Name, 150 is
Topical Heading, etc.  To put this in context:

<skos:Concept rdf:ID="Cats--France">
 <skos:prefLabel>Cats--France</skos:prefLabel>
</skos:Concept>

<skos:TopConcept>
  <skos:prefLabel>Topical</skos:prefLabel>
  <skos:narrower rdf:resource="#Cats--France"/>
</skos:TopConcept>

For LCSH, the Topical skos:TopConcept could have several
hundered thousand skos:narrower elements.  Not very
scalable.  A better arrangement might be:

<skos:Concept rdf:ID="Cats--France">
 <skos:prefLabel>Cats--France</skos:prefLabel>
 <skos:inFacet rdf:resource="#Facet-Topical"/>
</skos:Concept>

<skos:Facet rdf:ID="Facet-Topical">
  <skos:prefLabel>Topical</skos:prefLabel>
</skos:TopConcept>


Andy.

Andrew Houghton, OCLC Online Computer Library Center, Inc.
http://www.oclc.org/about/
http://www.oclc.org/research/staff/houghton.htm

Received on Thursday, 13 May 2004 13:00:57 UTC