Re: RDF test case on datatypes

On Thu, 28 Aug 2003, Olivier Corby wrote:

> OK, and with the following triples where it is explicitely stated that
> xsd:decimal and xsd:string ARE datatypes, is it still not false in an
> XSD-sensitive interpretation ?
>
> ex:foo ex:bar     ex:gee
> ex:gee rdf:type   xsd:decimal
> ex:bar rdfs:range xsd:string
>
> xsd:decimal rdf:type rdfs:Datatype
> xsd:string  rdf:type rdfs:Datatype

There is no satisfying RDFS+D(xsd:decimal, xsd:string)-interpretation;
however, for a reasoner to figure this out it would need to know that
xsd:decimal and xsd:string have nonintersecting value spaces. While it's
quite possible to build such knowledge into a reasoner, there is no
mechanism within _RDFS_ to be able to explicitly state (using triples)
that the class extensions of xsd:decimal and xsd:string are disjoint, so
such a conclusion (while valid), would come from "built-in" knowledge
about the datatypes.

OWL DL does provide this expressive capability.

-- 
jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
Tel +44(0)117 9287088 Fax +44 (0)117 9287112 http://ioctl.org/jan/
Semantic rules, OK?

Received on Friday, 29 August 2003 05:16:21 UTC