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Subject: Re: Secrets of Rybka and Fruit from my point of view

Author: Ryan B.

Date: 18:14:17 12/15/05

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On December 15, 2005 at 19:57:45, Uri Blass wrote:

>On December 15, 2005 at 19:38:51, Stuart Cracraft wrote:
>>On December 15, 2005 at 19:18:37, Uri Blass wrote:
>>>I also agree and I never underestimated fruit's evaluation.
>>>It is possible that the main reason for it's superior evaluation is the idea of
>>>average between opening and endgame but it is fact that it has a superior
>>Really? Just the line from fruit:eval.c:
>>  eval = ((opening * (256 - phase)) + (endgame * phase)) / 256;
>>I find that VERY hard to believe. That concept has been around a
>>very long-time.
>I do not read much source code of free programs so I do not know but I wonder
>if free source code programs before fruit use that idea and have for every term
>endgame evaluation and opening evaluation.
>I use it for some things and I learned the idea from fruit but most of my
>evaluation does not use that idea and I may rewrite the evaluation and test.
>>You must propose something better.
>>Superior evaluation?
>>That code is trivially small.
>>So, small is beautiful?
>bigger has the potential to be better but it is not always better.
>I believe that Rybka's evaluation is even better than fruit's evaluation but
>fruit's evaluation is better than the evaluation of most top programs including

A strong point of Fruits eval is that it is more accurate than it is deep.  Many
people think they will have a better eval by having more knowledge but end of
having bad chess knowledge that does not work well this other knowledge in the


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