optimal aspiration window for stockfish question
Posted: Mon Mar 12, 2012 12:14 pm
Looking at analysis of stockfish of some position from correspondence game(I omit the moves and only show the scores)
you can see that the score at depth 35 is 1.97 and the score at depth 36
is 1.93 but for some reason stockfish has many fail low and fail high during the process(this is not something rare and the same happened also at depth 24 of the same search).
I wonder if it is not better to start with bigger difference between alpha and beta with big depth and if the programmers tried to optimize the difference between alpha and beta in stockfish as a function of depth.
Did somebody in the stockfish team tested to find the size of the optimal window for different depths to see if it is not better to change it.
35/79 40:24 10,618,711,296 4,378,972 +1.97
36/79- 42:46 11,265,468,653 4,388,811 +1.89
36/79- 43:36 11,486,371,530 4,389,792 +1.81
36/79- 44:35 11,747,022,497 4,390,999 +1.69
36/79+ 46:55 12,371,982,241 4,393,810 +2.06
36/79 55:58 14,833,537,002 4,417,125 +1.93
earlier from the same search
23/56 00:36 130,367,750 3,606,399 +1.37 24/56+ 00:43 158,498,424 3,604,776 +1.45 24/56- 00:46 169,841,034 3,623,584 +1.29 24/56- 00:47 172,222,913 3,627,349 +1.17
24/56- 00:48 175,065,644 3,613,624 +0.98 24/56+ 00:50 183,805,380 3,619,356 +1.53
24/64 01:03 231,112,085 3,634,123 +1.37
you can see that the score at depth 35 is 1.97 and the score at depth 36
is 1.93 but for some reason stockfish has many fail low and fail high during the process(this is not something rare and the same happened also at depth 24 of the same search).
I wonder if it is not better to start with bigger difference between alpha and beta with big depth and if the programmers tried to optimize the difference between alpha and beta in stockfish as a function of depth.
Did somebody in the stockfish team tested to find the size of the optimal window for different depths to see if it is not better to change it.
35/79 40:24 10,618,711,296 4,378,972 +1.97
36/79- 42:46 11,265,468,653 4,388,811 +1.89
36/79- 43:36 11,486,371,530 4,389,792 +1.81
36/79- 44:35 11,747,022,497 4,390,999 +1.69
36/79+ 46:55 12,371,982,241 4,393,810 +2.06
36/79 55:58 14,833,537,002 4,417,125 +1.93
earlier from the same search
23/56 00:36 130,367,750 3,606,399 +1.37 24/56+ 00:43 158,498,424 3,604,776 +1.45 24/56- 00:46 169,841,034 3,623,584 +1.29 24/56- 00:47 172,222,913 3,627,349 +1.17
24/56- 00:48 175,065,644 3,613,624 +0.98 24/56+ 00:50 183,805,380 3,619,356 +1.53
24/64 01:03 231,112,085 3,634,123 +1.37