Re: Fragments - specific proposal

From: Carsten Lutz <clu@tcs.inf.tu-dresden.de>
Subject: Re: Fragments - specific proposal
Date: Mon, 10 Dec 2007 12:00:43 +0100 (CET)

> On Mon, 10 Dec 2007, Ivan Herman wrote:
> >
> > Carsten Lutz wrote:
> >>
> >> Hi Jim,
> >>
> >> On Fri, 7 Dec 2007, Jim Hendler wrote:
> >>
> >>> 2 - RDFS 3.0
> >>> I propose we name a subset called RDFS 3.0 which is less than OWL Lite
> >>> - aimed primarily at universals - i.e. named classes and properties,
> >>> no restriction statements involved.
> >>> There should be a version of this which is provably polynomial within
> >>> certain restrictions (at least no redefinition of the language
> >>> features, possibly
> >>
> >> Then it would IMHO be appropriate if some of the supporters of RDFS
> >> 3.0 would state precisely what this tractable fragment is and prove
> >> that it is tractable. Otherwise, I feel I am discussing a ghost.
> >>
> >
> > I think Jim refers to:
> >
> > http://www.w3.org/2007/OWL/wiki/Fragments
> >
> > which posted some times ago.
> 
> Thanks, I know that page. But to me Jim's remark doesn't sound as if
> referring to that page.  He says that "There should be a version of
> this which is provably polynomial". Since I think that polynomiality
> is a very important property for fragments of OWL, I would like to
> understand what precisely that version is. Is it the one on the page
> you refer to? If not, what exactly does it look like?
> 
> greetings,
>  		Carsten

As well, http://www.w3.org/2007/OWL/wiki/Fragments does not provide a
definition of RDFS 3.0, just a set of vocabulary terms.  One cannot
expect that RDFS 3.0 is the syntactic subset of OWL Full using just
these terms, because of the appeal to OWL Prime, which is decidedly
*not* just a syntactic subset of OWL Full.  Before RDFS 3.0 can be
evaluated there needs to be a complete definition of what it is.

Peter F. Patel-Schneider
Bell Labs Research

Received on Monday, 10 December 2007 11:22:24 UTC