W3C home > Mailing lists > Public > public-swbp-wg@w3.org > January to March 2004

RE: [OPEN] and/or [PORT] : a practical question

From: Bernard Vatant <bernard.vatant@mondeca.com>
Date: Wed, 24 Mar 2004 01:19:51 +0100
To: "SWBPD" <public-swbp-wg@w3.org>
Message-ID: <GOEIKOOAMJONEFCANOKCKEOODJAA.bernard.vatant@mondeca.com>

> >- Is it worth the trade-off to switch one's ontology (otherwise DL)
> >to OWL-Full, just to
> >allow its classes to be used as objects in 'dc:subject' predicates?

> That's a weird way to ask the question.  You mean, is it worth doing
> the extra work to break your naturally occuring model just so that
> you can be in DL?

The way I put it might seem weird indeed, but it's the way it was set in the real project
context (real world is weird). We had an OWL-DL ontology, and wanted to keep it so, and
suddenly after six months or so some user wants to be able to use a class as a subject of
a document ... which is one case out of one thousand, the 999 others using 'regular'
subjects. So using a class as subject of a document is not exactly 'naturally occuring'.
It's a borderline case - not to say a weird one :))

> I would argue this is indeed a BP issue, but probably for WORLD not
> for OPEN... we need to explain why and when you would do the extra
> work (and in every case we have explored it is extra work) to make
> sure your ontology is in the DL profile of OWL.

I suggested it might be in PORT scope, because it deals with the terminology vs ontology
general issue. For me the heart of the question is to know what it means to 'use a
concept' defined in a terminology (glossary, thesaurus, subject headings, index...) as a
class (or a property) in an ontology.

Is 'PhD Thesis' class the same 'subject' (using TM language here, sorry) or 'resource'
than the original concept? The more I think about it, the more I have to deal with it, and
the more I tend to say that they are distinct animals. Jim's PhD Thesis is an instance of
the class, but not of the concept. One subject of 'Social Functions of PhD Thesis in
Occidental University during 20th century', is the concept of PhD Thesis, not the class.

So it's not just an issue of OWL-DL vs OWL-Full, it's also an issue of making distinct or
not those two 'things'. This is a core issue in porting thesaurus to the SW, related to
others of the same kind, like if concepts A and B are interpreted as classes, and there is
a Broader-Narrower relationship between A and B in the Thesaurus, has it to be interpreted
as a class-subclass relationship in the ontology etc.

So I think in that case a BP definition would be two-fold

1. Is it generally a BP to make terminology concepts distinct from ontology classes (and
2. If agnostic about 1, what is the trade-off when choosing to make them distinct or to
merge them ?

FWIW, having tried both terms of the alternative in the course of time, my personal view,
for above quoted reasons, is that they shoud be kept separate, and it's worth the extra
work (even before being aware of the DL vs Full issue)

Are there other concrete experience on that, not only theoretical considerations? Seems
like there are not so many people exploring the terminology-ontology interoperability. Or
are they?

Bernard Vatant
Senior Consultant
Knowledge Engineering
Mondeca - www.mondeca.com
Received on Tuesday, 23 March 2004 19:22:59 EST

This archive was generated by hypermail pre-2.1.9 : Tuesday, 23 March 2004 19:23:02 EST