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number of counter examples

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Posted on: Sun, 10/25/2009 - 11:41
Redbeard
Joined: 2009-10-25
Points: 6
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number of counter examples
Is there a shortcut way to find the number of counterexamples to a check?  I'm considering using Alloy for some evolutionary computation experiments.  However, that requires massive computation.  To be able to say one model is better than another, even though both are wrong, I'm looking at using the number of counterexamples.  I'm trying to figure out if this is feasible, or am I going to burn up far too much computer time attempting to tally counterexamples?
Ken Horne
Michigan State University
 
Posted on: Mon, 10/26/2009 - 08:24    #1
Felix Chang
Joined: 2008-05-15
Points: 334
User is offline
Hi: Unfortunately no. As we display each solution, we modify
the constraint problem behind the scene to make it
more constrained (so as to rule out the solution just displayed).
So we cannot know the exact number until we solve it to the end.
Also, as the problem becomes more and more constrained, it becomes
slower and harder to solve. So the last mile can be difficult.
 
Posted on: Mon, 10/26/2009 - 12:10    #2
Redbeard
Joined: 2009-10-25
Points: 6
User is offline
Thank you very much for your help, that clears things up.  The detail you gave helped and may allow me to come up with a way to make this work anyway.

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