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Subject: Re: Crafty Static Evals 2 questions

Author: Sune Fischer

Date: 02:59:16 02/27/04

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On February 27, 2004 at 05:43:48, Uri Blass wrote:

>I can add that I also have discontinuity and I see no special problems with it.
>I also have discontinuity from middlegame to endgame and I have different piece
>square tables for the king in the middle game and the endgame.

I think what could be a potential problem is if you create a zig-zag behavior of
the scores.

If you use a very un-smooth eval there is a chance it will create local optimums
here and there and the engine can get stuck in one of those if the search can't
see beyond to a better optimum.

It might also destabilize the search, not sure about that :)

Bob might be right that discontinuites can be a trouble maker in this respect.

>It is possible that I can do my program better by not doing it.
>The problem is that changing things without bugs is not a simple task when the
>piece square table score is part of the evaluation that is changed incrementally
>after every move(I thought when I started to have incremental evaluation but I
>gave up that idea not because I think that it is a bad idea but because I do not
>consider myself good enough to implement things fast without bugs but part of
>the incremental evaluation is still there and I did not get rid of it when only
>the rest of the evaluation is calculated from scratch at every node).
>
>Movei does not use a lot of time for the evaluation so maybe it may be better to
>get rid of all the incremental evaluation.

I don't use incremental eval, not even piece squares :)

-S.

>Uri



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