W3C home > Mailing lists > Public > www-webont-wg@w3.org > May 2002

Re: LANG: compliance levels

From: Deborah McGuinness <dlm@KSL.Stanford.EDU>
Date: Wed, 01 May 2002 15:46:58 -0700
Message-ID: <3CD07062.A183A2BA@ksl.stanford.edu>
To: Jonathan Borden <jonathan@openhealth.org>
CC: Enrico Motta <e.motta@open.ac.uk>, www-webont-wg@w3.org
Correct - local restrictions can be used to express global restrictions as you
state.
that is not the issue under discussion - it is universally qualified local
restrictions vs. existentially qualified local restrictions.

I also would choose just local restrictions over global since global
restrictions help people to make overly general statements with their conceptual
models.
we get global restrictions however with rdf.

deborah

Jonathan Borden wrote:

> Enrico Motta wrote:
>
> > At 5:34 pm -0700 28/4/02, Deborah McGuinness wrote:
> > >
> > >  > Can't one define existentially qualified range restrictions by having
> > >>  local ranges + min-cardinality? Or are they something else?
> > >
> > >with universally qualified range restrictions  one can say things
> > >such as "all my
> > >children are doctors"
> > >and with min cardinality  one can say things such as "i have at
> > >least one child"
> > >but in combination that only allows one to say  I have at least one child
> and
> > >ALL my children are doctors.
> > >This DOES  imply that I have at least one child who is a doctor.
> > >BUT it does not allow you to state the full generality of
> > >existentially qualified
> > >range ...
>
> > ... At the same
> > time I suspect that the opposite is not true.  If I don't have
> > universally quantified local range restrictions, I would not know how
> > 'to fake' them using existentially quantified local restrictions.
> >
> > Correct?
>
> At the A'dam F2F, we discussed the fact that the only thing that is _ever_
> needed are local range restrictions, as global restrictions can be expressed
> as a "local" restriction on owl:Thing.
>
> Hence I'd favor only local restrictions, as these are, in my experience,
> alot easier to understand for most people, particularly those used to they
> way classes are defined for popular programming languages.
>
> Jonathan

--
 Deborah L. McGuinness
 Knowledge Systems Laboratory
 Gates Computer Science Building, 2A Room 241
 Stanford University, Stanford, CA 94305-9020
 email: dlm@ksl.stanford.edu
 URL: http://ksl.stanford.edu/people/dlm/index.html
 (voice) 650 723 9770    (stanford fax) 650 725 5850   (computer fax)  801 705
0941
Received on Wednesday, 1 May 2002 18:47:41 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:57:49 GMT