- From: Geoff Chappell <geoff@sover.net>
- Date: Wed, 12 Jan 2005 09:02:38 -0500
- To: "'Steve Gollery'" <sgollery@cadrc.calpoly.edu>
- Cc: <www-rdf-interest@w3.org>
> -----Original Message----- > From: www-rdf-interest-request@w3.org [mailto:www-rdf-interest- > request@w3.org] On Behalf Of Steve Gollery > Sent: Tuesday, January 11, 2005 12:59 PM > To: www-rdf-interest@w3.org > Subject: classification inferences based on owl:disjointWith > > > I'm using Jena with Racer as the DIG reasoner, using a test program > based on the "Extended example" at > http://jena.sourceforge.net/how-to/dig-reasoner.html. > > I have an ontology that imports foaf. After I load the ontology, I list > the OWL classes using OntModel.listClasses. The foaf classes don't show > up on the list, although they do appear when I list all the statements > with predicate "rdf:type" and object "rdfs:Class." It looks like Racer > is not inferring that the foaf classes are OWL classes, even though they > are defined like this: > > <rdfs:Class rdf:about="http://xmlns.com/foaf/0.1/Document" > rdfs:label="Document" rdfs:comment="A document."> > <rdfs:subClassOf > rdf:resource="http://xmlns.com/wordnet/1.6/Document"/> > <rdfs:isDefinedBy rdf:resource="http://xmlns.com/foaf/0.1/"/> > <owl:disjointWith > rdf:resource="http://xmlns.com/foaf/0.1/Organization"/> > <owl:disjointWith rdf:resource="http://xmlns.com/foaf/0.1/Person"/> > <owl:disjointWith rdf:resource="http://xmlns.com/foaf/0.1/Project"/> > </rdfs:Class> > > Since the domain and range of owl:disjointWith is owl:Class, I would > expect that an inference engine would classify foaf:Document as an > owl:Class even though the ontology states that foaf:Document is an > rdfs:Class. > > Am I wrong about that? No, I don't think so - that should be a valid inference (at least in owl full). Maybe the foaf ontology doesn't fit the syntactic restrictions that DLs require and so isn't imported properly (or at all)? > Steven Gollery > sgollery@cadrc.calpoly.edu Rgds, Geoff Chappell
Received on Wednesday, 12 January 2005 14:02:52 UTC