W3C home > Mailing lists > Public > public-swbp-wg@w3.org > April 2004

RE: [OEP] "Classes as values": comments on draft $swbp

From: Aldo Gangemi <a.gangemi@istc.cnr.it>
Date: Fri, 30 Apr 2004 10:10:41 +0100
Message-Id: <p06002002bcb7c7486463@[212.34.219.175]>
To: "Uschold, Michael F" <michael.f.uschold@boeing.com>
Cc: "Miles, AJ (Alistair) " <A.J.Miles@rl.ac.uk>, Jeremy Carroll <jjc@hplb.hpl.hp.com>, ewallace@cme.nist.gov, public-swbp-wg@w3.org, guarino@loa-cnr.it

Mike's argument is the same I held for WordNet. One thing is 
considering wordnets, thesauri, terminologies as informal ontologies, 
and then reengineering them to get full-fledged ontologies, and 
another thing is trying to describe their current structure. The 
second one can have interesting uses, provided that we do not mix 
ontologies and structures in the same domain. In the WordNet task 
force, we have decided to give recommendations for both things, and 
explaining the different results, advantages, and uses.

A

At 12:16 -0700 29-04-2004, Uschold, Michael F wrote:
>I like the first proposal. The second one may be exactly appropriate 
>in some circumstances, but I have a concern about it.  SKOS seems to 
>be an ontology representing the important things needed to represent 
>thesauri (i.e. it creates a sub-language for representing specific 
>thesauri.)  That is to say, the classes in SKOS represent language 
>constructs used to create thesauri, RATHER than representing things 
>in the world that are of interest (e.g. lions).  This distinction is 
>evident by using the name "LionConcept" rather than "Lion".  This 
>use of RDFS is as a meta-language, used to define a thesaurus 
>language.
>
>So the concern I have is mixing up use of RDFS/OWL as an ontology 
>language for representing domains directly, vs. a meta-language for 
>representing other representation languages/notations.
>
>A close analogy of this would be to say, use OWL (or RDFS) to 
>represent another ontology language. For example, we could create an 
>OWL ontology with classes that referred to Flogic language 
>constructs. e.g.  OWL classes named: 'FlogicCLass' and 
>'FlogicAttribute'...  This is a very different use of OWL, than 
>representing domains directly.  It is certainly not the main 
>intended use if OWL, and really is using OWL as a meta-language.
>
>Mike
>
>
>  -----Original Message-----
>From:	Miles, AJ (Alistair)  [mailto:A.J.Miles@rl.ac.uk]
>Sent:	Thursday, April 29, 2004 7:37 AM
>To:	Uschold, Michael F; Jeremy Carroll; ewallace@cme.nist.gov
>Cc:	public-swbp-wg@w3.org; guarino@loa-cnr.it
>Subject:	RE: [OEP] "Classes as values": comments on draft
>
>
>Sorry, resending this correcting some N3 syntax mistakes ...
>
>I believe the best way to express the fact that a particular image depicts a
>thing which is a member of the class of Lions would be to say (this is the
>FOAF model):
>
>LionImage
>	a	AnimalImage;
>	foaf:depicts	[a	Lion].
>
>Lion
>	a	owl:Class;
>	subClassOf	Mammal.
>
>Mammal	a	owl:Class.
>AnimalImage	a	owl:Class.
>
>
>The alternative way of expressing similar information is to use the
>dc:subject property along with the SKOS model [2] for describing concepts
>that are intended to act as 'subjects' or 'topics' for information
>resources.
>
>LionImage
>	a	AnimalImage;
>	dc:subject	LionConcept.
>
>LionConcept
>	a	skos:Concept;
>	skos:prefLabel	'Lions';
>	skos:broader	MammalConcept.
>
>MammalConcept
>	a	skos:Concept;
>	skos:prefLabel	'Mammals';
>	skos:narrower	LionConcept.
>
>The SKOS vocab already defines a class 'Concept' and a set of properties for
>organising concepts into a hierarchy, without demanding that the hierarchy
>implies a subclass relationship.  I refer the WG to the document [2] which
>outlines the SKOS-Core schema, although you should currently ignore the
>final section on 'using SKOS-Core with DC and FOAF' as this will change
>shortly to be in line with the model of usage that I have briefly described
>here.
>
>Yours,
>
>Alistair.
>
>[1]
>http://lists.w3.org/Archives/Public/www-archive/2004Apr/att-0061/ClassesAsVa
>lues.html
>[2] http://www.w3.org/2001/sw/Europe/reports/thes/1.0/guide/


-- 



*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*
Aldo Gangemi
Research Scientist
Laboratory for Applied Ontology, ISTC-CNR
Institute of Cognitive Sciences and Technologies
(Laboratorio di Ontologia Applicata,
Istituto di Scienze e Tecnologie della Cognizione,
Consiglio Nazionale delle Ricerche)
Viale Marx 15, 00137
Roma Italy
+3906.86090249
+3906.824737 (fax)
mailto://a.gangemi@istc.cnr.it
mailto://gangemi@acm.org
http://www.loa-cnr.it
Received on Friday, 30 April 2004 04:11:13 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:17:11 GMT