I inadvertently left trailing puncutation on the ends
of URL's. I've deleted it below. Apologies for any
inconvenience.

Tom

--- In algorithm-forge@y..., "threesat2000" <threesat2000@y...> wrote:
> --- In algorithm-forge@y..., "hpguo_2000" <hpguo@c...> wrote:
> > I'm looking for some 3SAT phase transition data. I've tried
running
> > OKGenerator and OKSlover to generate some, but they don't look
very
> > good. Could somebody please point me to somewhere ? Thanks a lot!
> >
> > cheers,
> > -hpguo
>
> The answer depends a lot on what you want to use the data for.
> Are you looking for hard problems to solve near the transition
> to validate a SAT solver? Or do you want problems surrounding
> the transition to study the transition itself?
>
> The uniform random 3SAT problems in the benchmark section of
> http://www.satlive.org are taken at or near the transition
> point. The compressed files contain thousands of satisfiable
> and unsatisfiable instances of various sizes.
>
> Before you try anything with random problems, be sure to read
> "Some Pitfalls for Experimenters with Random SAT" by David G.
> Mitchell and Hector J. Levesque, downloadable from Citeseer at
>
> http://citeseer.nj.nec.com/mitchell96some.html
>
> Another excellent SAT site for discussions, references to
> current work, etc., is Daniel Le Berre's
>
> http://www.satlive.org
>
> For comparisons of the performance of the best current SAT
> solvers, see Laurent Simon's SatEX site at
>
> http://www.lri.fr/~simon/satex/satex.php3
>
> Simon has also provided links to some particularly challenging
> problems.
>
> Good luck! We'd like to know more about what you are doing.
> Why don't you post a short description?
>
> Tom