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Re: [Fwd: RE: LANG: compliance levels]

From: Deborah McGuinness <dlm@KSL.Stanford.EDU>
Date: Sat, 27 Apr 2002 16:37:02 -0700
Message-ID: <3CCB361E.CF563871@ksl.stanford.edu>
To: www-webont-wg@w3.org


Frank van Harmelen wrote:

> -------- Original Message --------
> Subject: RE: LANG: compliance levels
> Date: Thu, 25 Apr 2002 12:38:05 +0300
> From: "Ziv Hellman" <ziv@unicorn.com>
> To: "Frank van Harmelen" <Frank.van.Harmelen@cs.vu.nl>,"Mike Dean" <mdean@daml.org>,"Enrico Motta" <E.Motta@open.ac.uk>,"Ian Horrocks" <horrocks@cs.man.ac.uk>,<herman.ter.horst@philips.com>,"Peter Patel-Schneider" <pfps@research.bell-labs.com>,"Christopher Welty" <welty@us.ibm.com>,"Jim Hendler" <hendler@cs.umd.edu>,"Raphel Volz" <rvo@aifb.uni-karlsruhe.de>,"Deborah McGuinness" <dlm@ksl.stanford.edu>
> CC: <www-webont-wg@w3.org>
>
> Two comments:
>
> 1) Please provide more detail as to exactly what you intend by stating
> 'functionality of properties'
>

functionality of roles in our proposal is equivalent to stating   an at most 1 restriction.
(thus the role has either 0 or 1 filler but no more).
It also abides by the same side condition as exists in DAML+OIL - ie., it is not allowed to state that a role is simultaneously functional AND transitive.

>
> 2) As recent email exchanges on the WebOnt forum indicate, the
> distinction between primitive and defined classes can be tenuous, at
> least with full DAML+OIL expressiveness. Will the same be true of
> compliance level 1 of OWL?

I guess I need more detail on the tenuous nature of defined/primitive distinction in order to address this question.
I think we do not have a choice in daml+oil/owl/fowl but to solve the issue of grouping statements somehow and thus will have a mechanism for grouping an entire term definition together thus solving the problem of potentially having sufficiency conditions for membership in multiple places in a knowledge base.  If this problem is solved, do you still have other problems with the primitive/defined class
distinction?

Deborah

>

> >-----Original Message-----
> >From: Frank van Harmelen [mailto:Frank.van.Harmelen@cs.vu.nl]
> >Sent: Monday, 22 April, 2002 18:28
> >To: Mike Dean; Enrico Motta; Ziv Hellman; Ian Horrocks;
> >herman.ter.horst@philips.com; Peter Patel-Schneider;
> >Christopher Welty; Jim Hendler; Raphel Volz; Deborah McGuinness
> >Subject: Re: LANG: compliance levels
> >
> >
> >(Sorry to some of you for resending this, but some people fell
> >of the original addresslist of this msg). Please reply to this
> >copy to make sure your reply reaches all.
> >
> >----
> >
> >A small group met at KR'02 (ter Horst, Patel-Schneider,
> >Horrocks, Welty, McGuinness, van Harmelen), discussing the
> >contents of compliance level 1 for OWL. We solicit reactions
> >from those volunteered for this task. Please do this by
> >immediate response, so that we can report back to the WG next
> >Thursday.
> >
> >We propose to use for level 1 RDF Schema on Steroids,
> >(using the terminology from Frank's Thursday 18 April message)
> >with additionally:
> >- properties can be declared functional
> >- datatypes (details depending on resolution by RDF Core).
> >
> >The main motivation for this choice is aimed at tool developers:
> >this level gives tool developers a useful language to aim at
> >that is significantly smaller than DAML+OIL, while imposing as
> >few restrictions as possible on toolbuilders that want to
> >extend beyond this compliance level. Putting in any additional
> >features (such as universal local range restrictions) into
> >level 1 will make it much harder to go beyond this basic level
> >(for example the interaction with existential restrictions).
> >
> >Written out in full, this amounts to:
> >
> >RDF Schema stuff
> >    primitiveclass
> >    subClassOf
> >    subpropertyof
> >    domain
> >    range
> >    Property
> >    named & unnamed Individual
> >
> >(In)equality
> >    sameClassAs
> >    samePropertyAs
> >    sameIndividualAs
> >    differentIndividualAs
> >
> >Property characteristics
> >    inversOf
> >    transitive
> >    symmetric
> >
> >Plus: functionality of properties (= at most one value for a property)
> >      (with the usual side condition that this cannot be applied to
> >       transitive properties, same side condition as in DAML+OIL)
> >plus: datatypes (unclear at this moment what this means precisely,
> >      pending on RDF Core decisions.
> >
> >
> >Frank,
> >Deborah.
> >   ----
> >
> >

--
 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
 (voice) 650 723 9770    (stanford fax) 650 725 5850   (computer fax)  801 705 0941
Received on Saturday, 27 April 2002 19:37:46 GMT

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