Re: common properties and rdfs:domain

Matt, that sounds correct. But in your schema, if you need title, identifier etc. properties that may be slightly different, wouldn't inheriting from dc:title give you what you need?  You can decide the different domains etc. for these properties...

Revi


----- Original Message ----
From: "Johnson, Matthew C. (LNG-HBE)" <Matthew.C.Johnson@lexisnexis.com>
To: semantic-web@w3.org
Sent: Wednesday, June 11, 2008 11:29:01 AM
Subject: common properties and rdfs:domain

 
Hi all,
 
When I originally read the RDFS spec some time ago, I
breezed over the concept of rdfs:domain with the assuredness of an OO
programmer that that the concept mapped nicely to my own conception of a class
(silly me).  Reading “Semantic Web for the Working Ontologist”
[1] has caused me to do a few double takes in my reading (my neck hurts now). 
I’d like to see if my understanding is now correct.
 
mysch:p1 rdfs:domain mysch:A .
myinst:me mysch:p1 “something” .
 
Would allow one to infer:
 
myinst:me rdf:type mysch:A .
 
without explicitly providing that triple.
 
Furthermore, an additional domain statement of:
 
mysch:p1 rdfs:domain mysch:B .
 
would cause:
 
myinst:me rdf:type mysch:B .
 
to also be inferred.
 
Assuming this is good so far, is it safe to assume that one
should specify a class as a part of a property’s domain ONLY IF one is
prepared to say that all subjects that use that property are in ALL of the
classes specified by the domain regardless of whether that typing is explicitly
stated?
 
My use-case that started this is common/generic properties
such as Dublin Core’s “dc:title”, “dc:identifier”,
etc.  My original OO-inspired approach had me explicitly stating the domain
of these properties [within my schema] based on classes that might use them. 
Since this was just a sandbox for me, no harm was done but I now believe that I
was incorrectly providing class inferences based those domain statements. 
My thinking now is that these types of properties should really never have a
domain specified since it is very likely that such properties will be used on a
wide variety of classes.  Is there a flaw in this statement?
 
Thanks in advance for your thoughts on this.
 
Matt
 
 
 
 
 
 
 
[1] Dean Allemang and Jim Hendler. 2008.