Re: Examples of OWL used for datatype inferencing?

Thanks.  Your [1] has some of the sort of discussion I was after, even if 
it does contain a lot of theoretical detail that I'm not ready to tackle at 
this time.   It tends to confirm my impression that some additional 
machinery is needed to handle datatype inference.  I'm trying to figure how 
little one might get away with.

I like the way this approach appears to separate datatype handling from 
other aspects of the inference process.

#g
--

At 10:44 02/11/03 +0000, Ian Horrocks wrote:
>OWL's datatype support is currently fairly rudimentry and does not
>include any means of expressing the kinds of knowledge you
>describe. One way to do so, while still maintaining decidability (for
>OWL DL at least) would be to extend the language with n-ary datatype
>predicates (see, e.g., [1]). Another way would be to include
>arithmetic built-ins in an expressive extension such as horn rules
>(see, e.g., [2]), but this would almost certainly make the language
>undecidable.
>
>Ian
>
>[1] http://www.cs.man.ac.uk/~horrocks/Publications/download/2003/PaHo03a.pdf
>[2] http://www.cs.man.ac.uk/~horrocks/DAML/Rules/
>
>
>On October 31, Graham Klyne writes:
> >
> > [I originally asked this on RDF-IG, but realize this is probably the 
> better
> > forum. #g]
> >
> > Does anyone have any examples of using OWL to perform RDF-datatype-related
> > inferencing?
> >
> > I'm thinking of datatypes, such as numbers, for which additional 
> properties
> > are used to define additional relations, such as addition over numbers.
> >
> > For example, given:
> >
> >     :vehicle :seatedCapacity "30"^^xsd:integer .
> >     :vehicle :standingCapacity "10"^^xsd:integer .
> >
> > and knowledge that the total capacity is seated capacity + standing
> > capacity, that one might infer:
> >
> >     :vehicle :totalCapacity "40"^^xsd:integer .
> >
> > This might be expressed thus using CWM-style rules:
> >
> >     { ?v :seatedCapacity ?c1 .
> >       ?v :standingCapacity ?c2 .
> >       (?c1 ?c2) math:sum ?c3 . }
> > =>
> >     { ?v :totalCapacity ?c3 . }
> >
> > It seems to me that to express such relations one must have a form of
> > universal quantification.  But I'm not sure if anything in OWL performs
> > such a purpose, so I struggle to see how one might express an idea like
> > that above.
> >
> > Behind this question, I'm trying to see if there's a way to abstract the
> > rules of datatype properties away from particular application
> > domain.  (i.e. using just RDF statements, and not rules, to express ideas
> > like the example above, appealing only to application-independent rules
> > defined on datatyped values.)  Currently I'm not seeing any way to do 
> this,
> > but before I give up I wanted to see how OWL (as the major thrust for Sweb
> > inference) deals with such issues.
> >
> > #g
> >
> >
> > ------------
> > Graham Klyne
> > For email:
> > http://www.ninebynine.org/#Contact

------------
Graham Klyne
For email:
http://www.ninebynine.org/#Contact

Received on Monday, 3 November 2003 10:57:27 UTC