Re: Relationships in SKOS Schemes

On Tue, Nov 28, 2006 at 05:21:18PM +0000, Sean Bechhofer wrote:
>          A question this raises to me is exactly how we intend to  
> specify SKOS. The SKOS guide describes SKOS as an application of RDF  
> that can be used to express a concept scheme. The presentation of the  
> SKOS "model" is done through the presentation of the RDF vocabulary  
> used.
> 
> An alternative could be to provide some more abstract model of what  
> SKOS vocabularies are and then a mapping into RDF triples that  
> provides the interchange format. This would be similar to
> the way that OWL was defined, with an abstract syntax and then a  
> mapping into the underlying triples representing the structure. Again  
> referring to the OWL 1.1 effort [1], this is being done using UML  
> diagrams to describe what's "in" the ontology. I believe doing things  
> this way can be of benefit in providing a "clean" underlying model  
...

Sean,

See also how this is done with Dublin Core.  There is a vocabulary
of properties and classes [1].  Then there is the DCMI Abstract Model [2],
currently under revision [3,4].  Then there are specifications for
expressing DCAM-based metadata in RDF [5] or in XML [6].  As one of its authors
explains DCAM in a recent blog posting [7]:

     * it describes an abstract information structure, the description
       set, in terms of the components which make up that structure
       (description, resource URI, statement etc) and the relationships
       between those components (a description set contains one or more
       descriptions; a description contains one or more statements;
       and so on)

     * it describes how an instance of that structure is to be interpreted,
       in terms of "what it says" about "things in the world" (each statement
       in a description "says" that the described resource is related in
       the way specified by (the resource identified by) the property URI
       to another resource; and so on)

By analogy, the abstract information structure to be described in 
in SKOS is the Concept Scheme.  In the current SKOS
document set -- Guide [8], Vocabulary Spec [9], and Quick Guide [10],
as listed in Deliverables [11] -- the Vocabulary Spec [9] says it is
"expressing the basic structure and content of concept schemes", but the
model of a Concept Scheme is not laid out as explicitly as it might be.

Sean, is that what you mean by an abstract model of "SKOS vocabularies"?

Tom


[1] http://dublincore.org/documents/dcmi-terms/
[2] http://dublincore.org/documents/abstract-model/
[3] http://dublincore.org/architecturewiki/AMDraftUpdate
[4] http://dublincore.org/architecturewiki/AbstractModelChanges
[5] http://dublincore.org/documents/dc-rdf/
[5] http://dublincore.org/documents/dc-xml/
[7] http://efoundations.typepad.com/efoundations/2006/11/why_an_abstract.html
[8] http://www.w3.org/TR/swbp-skos-core-guide/
[9] http://www.w3.org/TR/swbp-skos-core-spec/
[10] http://www.w3.org/TR/swbp-thesaurus-pubguide/
[11] http://www.w3.org/2006/07/SWD/wiki/Deliverables


-- 
Tom Baker - tbaker@tbaker.de - baker@sub.uni-goettingen.de

Received on Wednesday, 29 November 2006 08:29:48 UTC