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Subject: Evaluation function question

Author: Russell Reagan

Date: 17:01:39 06/17/02


I'd like to know how many people have to add in a lot of special case code to
their evaluation function(s). For example, does your king safety code in your
evaluation function make your program want to castle, or do you have to add in
code that penalizes the program if it hasn't castled? I suppose I'm wanting to
know how many people have a "natural" evaluation function that takes care of
these kinds of special cases without those cases having to have an extra "work
around" to work.

Secondly, do you think either approach is superior to the other? I think the
"natural" method would seem to be better. For example, if you reach an endgame
and castling still happened to be legal, and your program castles to get rid of
the "non-castling" penalty, even though your king should be trying to get
centrally located in the middle of the board. If your program had "king safety"
factors instead of the castling work around, then it wouldn't castle and would
play a more correct move. Seems pretty straight forward to me, but I've been
wrong before.

Other examples could be using a piece-square table with low values for the
border squares and high values for the central squares so that the program
"controls the center" in the opening. Or penalizing pieces that haven't moved
yet in the opening, or penalizing pieces that have moved more than once, etc.
These seem to be very poor methods of approaching an evaluation function at
first thought, but I haven't worked extensively on my own yet, so I'm no expert
here.

I'd like to know your thoughts...

Russell



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