Re: less-restrictive range and domain terms

From: Benja Fallenstein <b.fallenstein@gmx.de>
Subject: Re: less-restrictive range and domain terms
Date: Tue, 04 May 2004 18:54:10 +0200

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> Peter F. Patel-Schneider wrote:
> |>I've recently found myself wanting a less-restrictive version of
> |>rdfs:range (or owl:allValuesFrom) and rdfs:domain. I want to say
> |>'property *can* have range of class foo' rather than 'property *must*
> |>have range of class foo'.
> |
> | Hmm.
> |
> | First of all, there is no 'property *must* have range of class foo' in RDF
> | or OWL.  All there is is ``property *has* range class foo''.
> |
> | Second, what do you mean by 'property *may* have range of class foo'?
> 
> "There exist triples with property P and an object of class foo," rather
> than "All triples with property P have objects of class foo," is a
> useful interpretation, I presume.

But this is even expressible in RDF (at least for non-datatypes)

    _:x P _:y .
    _:y rdf:type foo .

> | So, show us the inferences!
> 
> ~    flabber x:schnack ghasted
> ~    ghasted rdf:type y:Ghostly
> 
> =====>
> 
> ~    x:schnack phil:rangeIncludes y:Ghostly

This is *one* inference.  What about the others?  Are there any?

> - - Benja
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Peter F. Patel-Schneider
Bell Labs Research

Received on Tuesday, 4 May 2004 13:45:48 UTC