Dev Builds » 20200220-0732

Use this dev build

NCM plays each Stockfish dev build 20,000 times against Stockfish 15. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds.

Summary

Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo
ncm-dbt-01 06:26:47 584388 4002 54 2578 1370 -257.99 ± 6.62 604 1316 81 0 0 -673.96 ± 38.4
ncm-dbt-02 06:24:54 585961 4000 62 2616 1322 -262.53 ± 6.87 637 1282 79 2 0 -669.55 ± 38.89
ncm-dbt-03 06:25:57 585434 4000 56 2616 1328 -263.42 ± 6.85 640 1280 80 0 0 -676.07 ± 38.65
ncm-dbt-04 06:26:49 567155 4010 39 2625 1346 -266.31 ± 6.77 646 1294 65 0 0 -713.25 ± 43.05
ncm-dbt-05 06:27:10 583915 3988 53 2588 1347 -260.87 ± 6.62 610 1316 67 1 0 -701.73 ± 42.37
20000 264 13023 6713 -262.21 ± 3.02 3137 6488 372 3 0 -686.1 ± 17.71

Test Detail

ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN
470928 ncm-dbt-01 583698 2 0 2 0 -1041.08 ± 395.59 1 0 0 0 0 -1129.65 ± 376.02
470926 ncm-dbt-04 566533 10 0 5 5 -190.62 ± 11.11 0 5 0 0 0 -1199.83 ± 231.31
470925 ncm-dbt-05 585674 488 5 308 175 -252.4 ± 17.14 65 173 6 0 0 -761.9 ± 187.95
470924 ncm-dbt-03 585674 500 9 335 156 -270.57 ± 20.56 87 152 11 0 0 -659.13 ± 116.77
470923 ncm-dbt-04 568355 500 2 337 161 -281.67 ± 20.45 91 153 6 0 0 -766.17 ± 188.02
470922 ncm-dbt-02 587579 500 9 325 166 -258.75 ± 19.63 78 161 10 1 0 -643.7 ± 122.54
470921 ncm-dbt-01 585885 500 6 319 175 -255.29 ± 17.54 70 173 7 0 0 -739.05 ± 163.27
470920 ncm-dbt-05 586520 500 9 328 163 -262.24 ± 19.26 79 161 10 0 0 -676.04 ± 124.55
470919 ncm-dbt-04 569549 500 7 329 164 -265.77 ± 19.69 82 158 10 0 0 -676.04 ± 124.55
470918 ncm-dbt-03 584243 500 7 325 168 -261.07 ± 19.11 78 162 10 0 0 -676.04 ± 124.55
470917 ncm-dbt-02 586731 500 8 324 168 -258.74 ± 19.36 78 160 12 0 0 -643.67 ± 110.29
470916 ncm-dbt-01 586308 500 2 318 180 -258.74 ± 17.98 73 170 7 0 0 -739.05 ± 163.27
470915 ncm-dbt-05 585000 500 3 332 165 -274.22 ± 19.27 84 161 5 0 0 -798.18 ± 231.48
470914 ncm-dbt-04 567482 500 4 329 167 -269.36 ± 18.98 81 163 6 0 0 -766.17 ± 188.02
470913 ncm-dbt-03 587367 500 8 331 161 -266.96 ± 20.39 85 153 12 0 0 -643.67 ± 110.29
470912 ncm-dbt-02 583824 500 6 318 176 -254.15 ± 18.24 72 168 10 0 0 -676.04 ± 124.55
470911 ncm-dbt-01 586562 500 7 322 171 -257.59 ± 18.68 75 165 10 0 0 -676.04 ± 124.55
470910 ncm-dbt-04 562612 500 5 339 156 -280.42 ± 20.9 92 150 8 0 0 -715.51 ± 146.53
470909 ncm-dbt-05 586054 500 8 326 166 -261.07 ± 19.92 81 156 13 0 0 -629.41 ± 104.8
470908 ncm-dbt-02 586477 500 10 340 150 -275.44 ± 21.15 91 148 11 0 0 -659.13 ± 116.77
470907 ncm-dbt-03 586774 500 9 324 167 -257.59 ± 19.49 78 159 13 0 0 -629.41 ± 104.8
470906 ncm-dbt-01 583237 500 10 327 163 -259.9 ± 19.78 80 157 13 0 0 -629.41 ± 104.8
470905 ncm-dbt-04 568037 500 3 314 183 -253.02 ± 18.1 71 169 10 0 0 -676.04 ± 124.55
470904 ncm-dbt-05 585674 500 9 320 171 -253.02 ± 18.37 72 167 11 0 0 -659.13 ± 116.77
470903 ncm-dbt-03 583740 500 3 333 164 -275.44 ± 18.8 83 164 3 0 0 -887.58 ± 222.18
470902 ncm-dbt-02 585084 500 5 336 159 -276.68 ± 20.45 89 153 8 0 0 -715.51 ± 146.53
470901 ncm-dbt-01 585928 500 5 325 170 -263.41 ± 18.84 78 164 8 0 0 -715.51 ± 146.53
470900 ncm-dbt-04 564723 500 6 313 181 -248.52 ± 17.25 66 175 9 0 0 -694.7 ± 134.18
470899 ncm-dbt-05 575232 500 5 332 163 -271.78 ± 20.15 85 158 6 1 0 -715.55 ± 177.2
470898 ncm-dbt-03 584369 500 8 322 170 -256.44 ± 19.07 76 162 12 0 0 -643.67 ± 110.29
470897 ncm-dbt-02 585843 500 9 309 182 -240.82 ± 16.51 60 180 10 0 0 -676.04 ± 124.55
470896 ncm-dbt-01 583824 500 6 332 162 -270.57 ± 19.71 84 158 8 0 0 -715.51 ± 146.53
470895 ncm-dbt-03 586774 500 6 334 160 -272.99 ± 19.72 85 158 7 0 0 -739.05 ± 163.27
470894 ncm-dbt-04 568355 500 5 330 165 -269.36 ± 19.28 82 161 7 0 0 -739.05 ± 163.27
470893 ncm-dbt-05 580738 500 5 329 166 -268.16 ± 18.84 80 164 6 0 0 -766.17 ± 188.02
470892 ncm-dbt-02 586858 500 6 332 162 -270.57 ± 20.0 85 156 9 0 0 -694.7 ± 134.18
470891 ncm-dbt-01 582527 500 12 316 172 -245.19 ± 18.92 71 162 17 0 0 -581.38 ± 88.96
470890 ncm-dbt-02 585295 500 9 332 159 -266.97 ± 20.39 84 156 9 1 0 -659.17 ± 131.36
470889 ncm-dbt-03 584537 500 6 312 182 -247.41 ± 17.92 68 170 12 0 0 -643.67 ± 110.29
470888 ncm-dbt-04 568752 500 7 329 164 -265.77 ± 19.41 81 160 9 0 0 -694.7 ± 134.18
470887 ncm-dbt-05 586435 500 9 313 178 -245.19 ± 17.09 64 176 10 0 0 -676.04 ± 124.55
470886 ncm-dbt-01 581527 500 6 317 177 -253.02 ± 18.37 72 167 11 0 0 -659.13 ± 116.77

Commit

Commit ID ab930f8d3f4a657f493305559756e85534c88911
Author protonspring
Date 2020-02-20 07:32:17 UTC
Updated KNNKP endgame. This is a patch that significantly improves playing KNNKP endgames: ``` Score of 2553 vs master: 132 - 38 - 830 [0.547] 1000 Elo difference: 32.8 +/- 8.7, LOS: 100.0 %, DrawRatio: 83.0 % ``` At the same time it reduces the evaluation of this mostly draw engame from ~7.5 to ~1.5 This patch does not regress against master in normal games: STC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 96616 W: 18459 L: 18424 D: 59733 Ptnml(0-2): 1409, 10812, 23802, 10905, 1380 http://tests.stockfishchess.org/tests/view/5e49dfe6f8d1d52b40cd31bc LTC LLR: 2.95 (-2.94,2.94) {-1.50,0.50} Total: 49726 W: 6340 L: 6304 D: 37082 Ptnml(0-2): 239, 4227, 15906, 4241, 250 http://tests.stockfishchess.org/tests/view/5e4ab9ee16fb3df8c4cc01d0 Theory: KNNK is a dead draw, however the presence of the additional weakSide pawn opens up some mate opportunities. The idea is to block the pawn (preferably behind the Troitsky line) with one of the knights and press the weakSide king into a corner. If we can stalemate the king, we release the pawn with the knight (to avoid actual stalemate), and use the knight to complete the mate before the pawn promotes. This is also why there is an additional penalty for advancement of the pawn. closes https://github.com/official-stockfish/Stockfish/pull/2553 Bench: 4981770
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