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Subject: Re: Verified Null-Move Pruning, ICGA 25(3)

Author: Uri Blass

Date: 18:50:52 11/21/02

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On November 21, 2002 at 21:39:06, Uri Blass wrote:

>On November 21, 2002 at 21:21:09, Vincent Diepeveen wrote:
>>On November 20, 2002 at 17:51:40, Alessandro Damiani wrote:
>>'verified' nullmove, or in a different implementation but
>>same algoritm, with just 1 ply reduction is nearly a fullwidth
>>I did with a bigger reduction of course. that's also very
>>costly compared to R=3. This was just an experiment carried
>>out years ago when it was described in ICCA journal. Now
>>we have same algoritm in a few lines diff algorithm.
>>I do not see how Omid can just suffer 50% slowdown of his
>>algorithm. Note he only publishes search depths not
>>search times. That is wrong.
>>You must publish search times.
>I do not see how you can suffer more than 50% slow down.
>I think that you simply do not understand the algorithm.
>The algorithm does not do nearly full width search because after the first
>reduction the search is normal null move pruning without verification.
>It did not work for movei or for sjeng but the difference is not as big as you
>describe and I suspect that with some modification it may work.

I can add that at least for movei I did not use the exact implementation as I
described in another post but I do not expect exact implementation to change a


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