[SKOS] Re: SKOS comment: Last Call Working Draft [ISSUE-182]

Dear Michael,

Thank you for your comments [1]:

2. Index terms

An important part of many classification systems is an index, in the
case of the DDC its "Relative Index". Index terms associated with a
given class generally reflect several of the topics falling within the
scope of that class. There is no easy way of modeling this relationship
in SKOS:

616 Diseases

Index terms:
Clinical medicine
Internal medicine
Physical illness--medicine

Currently, a possible workaround is to construct the complete Relative
Index as a separate skos:ConceptScheme and relate the concepts in these
two independent schemes by using mapping relations:

skosclass:hasIndexTerm rdfs:subPropertyOf skos:closeMatch .

skosclass:isIndexTermOf rdfs:subPropertyOf skos:closeMatch ;
owl:inverseOf skosclass:hasIndexTerm .

<class/616> a skos:Concept ;
skosclass:hasIndexTerm <index/Clinical%20medicine> ;
skos:inScheme <classification> .

<index/Clinical%20medicine> a skos:Concept ;
skosclass:isIndexTermOf <class/616> ;
skos:inScheme <index> .

This seems to be a satisfactory best-practice solution in this case, but
it has broader implications as index terms are just one instance of
Class-Topic Relations

SKOS does not indeed offer by default an exact solution to your problem. 

Our concern with this issue is that its scope might be 
limited, considering the general context of KOS practice. We have not 
identified that kind of situation in our Use Cases and Requirements 
document [2], even for the (UDC) classification case we had [3].

We consequently propose to *close* ISSUE-182 [ISSUE-182], making no 
change to the existing SKOS documents. *We hope that you are able to 
live with this.*

Please note that it is still possible to represent your "index terms", 
building on properties from SKOS and other existing vocabularies. 
Indeed, using a (specialization) of mapping properties, as you proposed, 
would seem very statisfactory.
Another option would be to use dc:subject (or a specialization of it), 
based on the observation that indexing of concepts or classes by other 
concepts or classes can be likened to indexing or classification of 
douments (or general resources).

I hope this helps. Note that whether you agree with one of the 
practices suggested here or come with a better solution, we encourage 
you to publish a brief note or a third-party extension proposal, and 
inform the SKOS community via the mailing list. This is important for 
us, and we'd be happy to set up a "community best practices" wiki page 
to collect links to such statements.

Best regards,


[ISSUE-182] http://www.w3.org/2006/07/SWD/track/issues/182
[1] http://lists.w3.org/Archives/Public/public-swd-wg/2008Oct/0061.html
[2] http://www.w3.org/2006/07/SKOS/UCR.html
[3] http://www.w3.org/2006/07/SWD/wiki/EucUDC

Received on Thursday, 6 November 2008 15:26:12 UTC