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TEST: maybe if/then is clearer than consistency? (more on sameGuy)

From: Dan Connolly <connolly@w3.org>
Date: 07 Mar 2002 12:58:10 -0600
To: www-webont-wg@w3.org, Ian Horrocks <horrocks@cs.man.ac.uk>
Message-Id: <1015527491.3230.29.camel@dirk>
I propsed tests consisting of a file of
premises and a file of conclusions...
an "if" file and a "then" file.

Ian, you pointed out that the usual way inference
systems do that sort of thing is to
negate the conclusion, assert the whole
thing, and ask if the result is consistent.

First question: does that always work?
is DAML+OIL closed under negation? How
do I negate a simple

	<page1> dc:title "ABC".
aka
	(dc:title page1 "ABC")
fact?

I guess the result looks like:
	(rdf:type page1
          (complementOf
             (onProperty dc:title hasValue "ABC")))
i.e. page1 is not in the class of things
that have "ABC" as a value of the dc:title property.

I still don't know if the whole language
is closed. Ian?

But in any case... the result is pretty
contorted. I'm working on taking the
conclusion of the sameGuy test and negating
it, and the tutorial value of the example
is going right out the window.

And the resulting test relies on not
just UnambiguousProperty, but also
onProperty/hasValue, intersectionOf,
lists, and all sorts of other features
that I didn't intend to test; i.e.
that my use case doesn't rely on.

So maybe there's a role for if/then
tests after all.

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Thursday, 7 March 2002 13:58:06 GMT

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