- From: Dan Connolly <connolly@w3.org>
- Date: 24 Jul 2002 12:26:35 -0500
- To: "Peter F. "Patel-Schneider <pfps@research.bell-labs.com>
- Cc: www-webont-wg@w3.org
On Wed, 2002-07-24 at 11:54, Peter F. Patel-Schneider wrote: [...] > Option 2: The sameXxxAs properties are not subproperties of equivalentTo. > > In this option the standard way of saying that two classes have the same > extension does not imply that they denote the same object. Here > sameClassAs is exactly the same as having two subClassOf relationships. > > This option does not depend on any particular answer to the classes as > instances issue. > > > > I vote for option 2. That's my preference for how sameClassAs works too. A couple test cases: first, an obvious one: :Car owl:sameClassAs :Automobile. :car1 rdf:type :Car. ==> :car1 rdf:type :Automobile. now, one that shows the distinction: :Car owl:sameClassAs :Automobile. :Car :averagePrice "20000". =?=> :Automobile :averagePrice "20000". Like Peter, prefer that this entailment does *not* old. Why? Because this is the minimally constraining design. And a third test, to give an example of the sorts of thing I do that we'd lose if we struck equivalentTo (and/or decided against classes as instances): :Car owl:equivalentTo :Automobile. :car1 rdf:type :Car. :Car :averagePrice "20000". :Automobile :averageWeight "2000". =?=> :car1 rdf:type _:someClass. _:someClass :averagePrice "20000". _:someClass :averageWeight "2000". I'm still thinking about whether I really, really need this in owl or not. If owl didn't provide it, I could probably make my own that's a subproperty of all three sameXXXAs. Sounds like Jeff H. and I would want to agree on how to spell it so our stuff could interoperate. Gee... sounds like it might be worth standardizing... 1/2 ;-) -- Dan Connolly, W3C http://www.w3.org/People/Connolly/ see you in Montreal in August at Extreme Markup 2002?
Received on Wednesday, 24 July 2002 13:26:29 UTC