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Evaluation weights

PostPosted: 27 Jun 2005, 11:25
by milix
Hi all.
I am in the process of rewriting my evaluation function. I will more or less have the same parameters as before (king safety, passed pawns, center control, mobility, pawn structure and some special patterns) but my main problem is how to weight these parameters. So far I used some general chess rules to begin with, like "a rook's pawn worth 80% of a central pawn"c. I am quite happy with my passed pawn eval. My main problem is how to tune the other weights, like mobility, center control, pawn shields, weak squares, bad bishops etc. I don't have time and computer power to play many computer-computer games to tune the parameters in actual game practice, so I must find another way for doing this. Are there any EPD suits that offer a clear presence of these positional characteristics? For example an EPD set that contains positions with bad bishops, a set that contains positions with bishop pair etc. Thanks in advance!

Re: Evaluation weights

PostPosted: 27 Jun 2005, 16:22
by Daniel Shawul
Hi!
LCTII is a good one. Positions 1-14 are positional tests which
include Rook on open/semi open file, Knight out post, bishop pair, mobility for bishops etc. I tuned my engine so that it will be able to solve
this positions with a reasonable time, doesn't have to solve them immediately.
daniel

Re: Evaluation weights

PostPosted: 27 Jun 2005, 18:11
by Pallav Nawani
I think Arasan 5 is also a good test suite.

Pallav