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Re: LANG: closing issue 4.6 (was Re: ADMIN: Draf agenda for July 25 telecon)

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
Message-Id: <1027531595.11038.183.camel@dirk>

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 GMT

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