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Subject: Re: Can nullmoves behave like this?

Author: Severi Salminen

Date: 11:17:47 01/08/01

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>i see you have 'futile moves' also. If you throw futility pruning out,
>then nullmove should work brilliant positionally spoken.

I tried, but the behaviour was the same. But then I removed my very stupid
3-fold repetition algorithm (it is only adding different bitboards of a position
to get a "key") and I got results with no fail highs or lows. I must find
another way to find repetitions...

>Otherwise you reduce depth and let opponent to move then you prune
>without trying the reduced depth even!
>Usually that's tactically not missing too much if you implement a few
>exceptions like allowing all captures, but it prunes positionally a lot!

What do you mean by allowing all captures? You mean excluding captures from
futility pruning - sounds odd?

>Nullmove definitely should give also in endgame about same PV and same
>score. Nullmove never can cause big problems, it can at most show
>existing problems.

Yes, advantages are _much_ greater than disadvantages, as you probably already
have noticed :)


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