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Re: The Ugly Test

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Sat, 01 Feb 2003 15:49:51 -0500 (EST)
Message-Id: <20030201.154951.68532744.pfps@research.bell-labs.com>
To: jos.deroo@agfa.com
Cc: jjc@hplb.hpl.hp.com, www-webont-wg@w3.org

From: "Jos De_Roo" <jos.deroo@agfa.com>
Subject: RE: The Ugly Test
Date: Sat, 1 Feb 2003 14:08:58 +0100

[...]

> >>   the range of p is one of 1,2,3,4
> >>   the range of p is one of 3,4,5,6
> >>   the range of p is one of 2,4,6,8
> >>   i is in a restriction on property p
> >>     with mincardinality of 2
> >
> >This is inconsistent and thus it entails
> >
> >>   i p 3
> >>   i p 4
> >
> >(but it is less interesting this time round!).
> 
> [T]hat's a nice reasoning. [H]mm...
> [S]o you would make it impossible to further make
> the range of a property sharper[.] ([D]oing so would
> make the kb inconsistent[.])

Huh?  it is certainly *possible* to make the KB inconsistent, so it is
certainly possible to further restrict the range of a property in this
case. 

> I believe that this is not following from AS&S[.]
> [A]t least I can't conclude it from such piece as
>   if E is rdfs:range
>   then for x element of IOP, y element of IOC U IDC
>   <x,y> element of EXTi(Si(E)) iff
>     <w,z> element of EXTi(x) -> z element of CEXTi(y)
> which we interpret as
>   {?x rdfs:range ?y. ?w ?x ?z} => {?z rdf:type ?y}.
>   {?z rdfs:subClassOf ?y. ?x rdfs:range ?z} => {?x rdfs:range ?y}.

Your system may not be able to make the inference, but it certainly does
follow from the semantics.

> [S]o I still think that we can't call the proposed testcase
> http://www.w3.org/2002/03owlt/oneOf/Manifest004#test a
> http://www.w3.org/2002/03owlt/testOntology#PositiveEntailmentTest

Why not?

> Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/

peter
Received on Saturday, 1 February 2003 15:50:07 GMT

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