trading pieces and pawns based on material balance

[jdart]

I do this rather simply:

if (opponent material value < 1/2 starting material && material difference >= Knight value (our side has more material))
scoring bonus = trade_down[opponent material units (not counting paws)]

trade_down is an array that gives more bonus as the opponent material drops (auto-tuned). Max bonus is about 1 pawn.

I also have special-case code for scoring drawish and drawn endgames, so this code is not executed for those cases.

--Jon

[Evert]

best thing is not to implement such a rule at all, as this is basically a purely human, psychological rule, mostly not available in stronger engines, as far as I can judge, and objectively bad/unreliable.

Having the value of pieces increase with game-phase has a similar effect to a trade bonus: advancing the game-phase by trading when you are ahead is good for you.