RE: [ALL] Requirements for updating OWL -- was FAQ : Constraints on data values range

The following came up in the context of OEP and UNITS however could be
relevant to ALL.

This is an interesting new twist on the role of the OEP group. Hitherto,
we have been setting out to give users information on how they can use
OWL to do various useful tasks.

Alan is now suggesting that to this we add another task, which naturally
follows: what things CANNOT be done easily or conveniently or AT ALL
using OWL. This can then be fed back to [?WHO?] at the W3C as
requirements for extensions/updates to OWL.

It makes a lot of sense to collect such examples as we go along. For
example, any notes that are put out that discover such cases, they
should be documented in that context. Also they could all be brought
together in a note unto itself as the WG progresses, or at the end.

This might be broader than the OEP task force. Some of the other task
forces may also discover such examples dictating changes to OWL.  It
could be a new Task Force that liased with all other Task Forces.

Just a few rambling thoughts...

Mike


-----Original Message-----
From: Alan Rector [mailto:rector@cs.man.ac.uk] 
Sent: Friday, April 30, 2004 8:10 AM
To: Jeremy Carroll
Cc: benoit.doumas@free.fr; public-swbp-wg@w3.org; Jeff Pan; Ian
Horrocks; Ulrike Sattler
Subject: Re: [UNITS, OEP] FAQ : Constraints on data values range


Jeremy, Guus, Bernard, All

I'd like to come in just to say that in a recent set of travels and
discussions with potential users of OWL, the inability to express
numeric constraints involving inequalities for things such as "Big
Wheel" etc. is a big problem.  Virtual all my biomedical examples
require normal values, value ranges, etc. which need this kind of
expressiveness .

To be blunt, there is no way that many potential users in these fields
will adopt OWL if it can't manage these 'simple' constraints.  As a
temporising measure, we may have to build some hybrid tools, but this is
not really satisfactory.

Jeff Pan and co are indeed working on formal solutions.  I think the
role of the best practices group should be to be sure that they have a
full set of requirements from the various applications against which to
test those solutions.  I've been having a considerable discussion with
them which I think has finally got past my misconceptions.

If we can gather together a good set of use cases and examples into a
summary paper, I think they would find that valuable - as I hope would
the group.

This is a place where the existing standard is inadequate to express
what users need.  I hope we can help get to the point to move it forward
with a clear set of user requirements - plus workarounds and help to
users not to 'bang their heads against the wall'.  Sometimes knowing
that something can't be done is almost as useful as knowing how to do
it.  Most users I have encountered have assumed it was their
misunderstanding rather than an intrinsic limitation in the language.

Regards

Alan




Jeremy Carroll wrote:

> > formal model. I recommend a paper "Web Ontology Reasoning with
> > Datatype Groups"
> > form J. Pan and I. Horrocks.
> > I think this is a problem that has to be explain in a FAQ.
> >
>
> I think that we currently have, in OWL, particularly OWL DL, and
> unnecessarily restrictive langauge for this problem. However, I am not
clear
> that enough industrial class apps are up with what datatype support
there is
> already in OWL, so I am in no hurry to move the goal posts towards
> expressivity.
>
> Some of Pan and Horrocks' work goes well beyond OWL expressivity and
looks
> really useful for the units stuff amongst others.
>
> I remain doubtful as to the scientific validity of the current
exclusion of
> inverse functional datatype properties (IFDP) in OWL DL, but didn't
make a
> song and dance about it at the appropriate time, and won't now either.
As
> far as I remember it is a complexity argument rather than a
decidability
> argument, and it seems to me that OWL DL + IFDP is of the same
complexity as
> OWL DL (maybe I have misunderstood; I've read the papers but couldn't
> reconstruct them).
>
> Jeremy

--
Alan L Rector
Professor of Medical Informatics
Department of Computer Science
University of Manchester
Manchester M13 9PL, UK
TEL: +44-161-275-6188/6149/7183
FAX: +44-161-275-6236/6204
Room: 2.88a, Kilburn Building
email: rector@cs.man.ac.uk
web: www.cs.man.ac.uk/mig
        www.opengalen.org
        www.clinical-escience.org

Received on Friday, 30 April 2004 18:33:17 UTC