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Re: classification inferences based on owl:disjointWith

From: Charles McCathieNevile <charles@w3.org>
Date: Wed, 12 Jan 2005 04:47:32 -0500 (EST)
To: Steve Gollery <sgollery@cadrc.calpoly.edu>
Cc: www-rdf-interest@w3.org
Message-ID: <Pine.LNX.4.55.0501120446280.18941@homer.w3.org>

I don't think the reasoner gets told rdfs:Class rdfs:subClass owl:Class in
which case it would have no reason to assume that foaf:Document is an
owl:Class...

cheers

Chaals

On Tue, 11 Jan 2005, Steve Gollery wrote:

>
>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?
>
>Steven Gollery
>sgollery@cadrc.calpoly.edu
>

Charles McCathieNevile             http://www.w3.org/People/Charles
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Received on Wednesday, 12 January 2005 09:47:33 GMT

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