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Subject: Re: No material count in Evalualtion idea

Author: Uri Blass

Date: 00:18:55 11/14/01

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On November 13, 2001 at 23:51:33, Chessfun wrote:

>On November 13, 2001 at 23:08:14, Robert Randolph wrote:
>
>>I am currently working on writing a new evaluation for my program.. I have been
>>contemplating an eval based on positional aspects and no direct material count.
>>
>>For instance, a white knight on H1 would be worth maybe .2, but a white knight
>>on E5 would be worth 3.2 Of course these are my actual eval values, but examples
>>to better iillustrate my idea.
>>
>>Has this been done before with any success, or lack there of?
>>
>>If it was a plausible idea (as i beleive it could be) what would your
>>suggestions be for positional advantages and disadvantages in this system, as
>>they would be fairly differing than those of evals that also rely on material
>>count.
>>
>>-Robert
>
>
>TSCP Tom's simple chess program eval.c seems to address this
>by adding the value of the location of the piece.
>
>If you have a look at eval.c you'll see the square value's
>Tom used.

Here is the piece square tables that Tom used
There is no doubt that they can be improved.

int knight_pcsq[64] = {
	-10, -10, -10, -10, -10, -10, -10, -10,
	-10,   0,   0,   0,   0,   0,   0, -10,
	-10,   0,   5,   5,   5,   5,   0, -10,
	-10,   0,   5,  10,  10,   5,   0, -10,
	-10,   0,   5,  10,  10,   5,   0, -10,
	-10,   0,   5,   5,   5,   5,   0, -10,
	-10,   0,   0,   0,   0,   0,   0, -10,
	-10, -30, -10, -10, -10, -10, -30, -10
};

Examples:
I think that a knight at a1 is even worse then a knight at b1

I also think that at a8 and h8 knights are often trapped so it is a good idea to
have -100 value for these squares or maybe even -150(I did not test it so I do
not know but -10 is clearly not negative enough).

a1 and h1 are also bad squares for knights and I guess that giving knights in
these squares -80 may be a good idea.


Uri



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