| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: nodchip
Date: Thu Aug 6 16:37:45 2020 +0200 Timestamp: 1596724665 Add NNUE evaluation This patch ports the efficiently updatable neural network (NNUE) evaluation to Stockfish. Both the NNUE and the classical evaluations are available, and can be used to assign a value to a position that is later used in alpha-beta (PVS) search to find the best move. The classical evaluation computes this value as a function of various chess concepts, handcrafted by experts, tested and tuned using fishtest. The NNUE evaluation computes this value with a neural network based on basic inputs. The network is optimized and trained on the evalutions of millions of positions at moderate search depth. The NNUE evaluation was first introduced in shogi, and ported to Stockfish afterward. It can be evaluated efficiently on CPUs, and exploits the fact that only parts of the neural network need to be updated after a typical chess move. [The nodchip repository](https://github.com/nodchip/Stockfish) provides additional tools to train and develop the NNUE networks. This patch is the result of contributions of various authors, from various communities, including: nodchip, ynasu87, yaneurao (initial port and NNUE authors), domschl, FireFather, rqs, xXH4CKST3RXx, tttak, zz4032, joergoster, mstembera, nguyenpham, erbsenzaehler, dorzechowski, and vondele. This new evaluation needed various changes to fishtest and the corresponding infrastructure, for which tomtor, ppigazzini, noobpwnftw, daylen, and vondele are gratefully acknowledged. The first networks have been provided by gekkehenker and sergiovieri, with the latter net (nn-97f742aaefcd.nnue) being the current default. The evaluation function can be selected at run time with the `Use NNUE` (true/false) UCI option, provided the `EvalFile` option points the the network file (depending on the GUI, with full path). The performance of the NNUE evaluation relative to the classical evaluation depends somewhat on the hardware, and is expected to improve quickly, but is currently on > 80 Elo on fishtest: 60000 @ 10+0.1 th 1 https://tests.stockfishchess.org/tests/view/5f28fe6ea5abc164f05e4c4c ELO: 92.77 +-2.1 (95%) LOS: 100.0% Total: 60000 W: 24193 L: 8543 D: 27264 Elo +92.77 Ptnml(0-2): 609, 3850, 9708, 10948, 4885 40000 @ 20+0.2 th 8 https://tests.stockfishchess.org/tests/view/5f290229a5abc164f05e4c58 ELO: 89.47 +-2.0 (95%) LOS: 100.0% Total: 40000 W: 12756 L: 2677 D: 24567 Elo +89.47 Ptnml(0-2): 74, 1583, 8550, 7776, 2017 At the same time, the impact on the classical evaluation remains minimal, causing no significant regression: sprt @ 10+0.1 th 1 https://tests.stockfishchess.org/tests/view/5f2906a2a5abc164f05e4c5b LLR: 2.94 (-2.94,2.94) {-6.00,-4.00} Total: 34936 W: 6502 L: 6825 D: 21609 Elo -3.21 Ptnml(0-2): 571, 4082, 8434, 3861, 520 sprt @ 60+0.6 th 1 https://tests.stockfishchess.org/tests/view/5f2906cfa5abc164f05e4c5d LLR: 2.93 (-2.94,2.94) {-6.00,-4.00} Total: 10088 W: 1232 L: 1265 D: 7591 Elo -1.14 Ptnml(0-2): 49, 914, 3170, 843, 68 The needed networks can be found at https://tests.stockfishchess.org/nns It is recommended to use the default one as indicated by the `EvalFile` UCI option. Guidelines for testing new nets can be found at https://github.com/glinscott/fishtest/wiki/Creating-my-first-test#nnue-net-tests Integration has been discussed in various issues: https://github.com/official-stockfish/Stockfish/issues/2823 https://github.com/official-stockfish/Stockfish/issues/2728 The integration branch will be closed after the merge: https://github.com/official-stockfish/Stockfish/pull/2825 https://github.com/official-stockfish/Stockfish/tree/nnue-player-wip closes https://github.com/official-stockfish/Stockfish/pull/2912 This will be an exciting time for computer chess, looking forward to seeing the evolution of this approach. Bench: 4746616 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stefan Geschwentner
Date: Fri Jul 31 10:12:54 2020 +0200 Timestamp: 1596183174 Tweak cutnode reduction Less reduction for second move at non-check CUT node with depth <= 10. STC: LLR: 2.94 (-2.94,2.94) {-0.50,1.50} Total: 38680 W: 7490 L: 7245 D: 23945 Elo +2.20 Ptnml(0-2): 643, 4441, 8967, 4606, 683 https://tests.stockfishchess.org/tests/view/5f21e1782f7e63962b99f451 LTC: LLR: 2.95 (-2.94,2.94) {0.25,1.75} Total: 71976 W: 9003 L: 8636 D: 54337 Elo +1.77 Ptnml(0-2): 440, 6414, 21972, 6663, 499 https://tests.stockfishchess.org/tests/view/5f2245762f7e63962b99f4bd closes https://github.com/official-stockfish/Stockfish/pull/2868 Bench: 4746616 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stéphane Nicolet
Date: Fri Jul 31 10:01:39 2020 +0200 Timestamp: 1596182499 Improve handling of queen imbalance We double the bonus for potential threats by minors and rooks against our queen, in case of "queen vs pieces imbalance". Hopefully this will improve a little bit the evaluation for this well-known Stockfish weakness. passed STC: LLR: 2.93 (-2.94,2.94) {-0.50,1.50} Total: 72976 W: 14003 L: 13710 D: 45263 Elo +1.39 Ptnml(0-2): 1218, 8370, 17094, 8513, 1293 https://tests.stockfishchess.org/tests/view/5efa50eb020eec13834a977d passed LTC: LLR: 2.93 (-2.94,2.94) {0.25,1.75} Total: 22232 W: 2779 L: 2560 D: 16893 Elo +3.42 Ptnml(0-2): 129, 1885, 6896, 2050, 156 https://tests.stockfishchess.org/tests/view/5f1fdd2dc09435d870cb9f13 closes https://github.com/official-stockfish/Stockfish/pull/2864 Bench: 4367349 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: UnaiCorzo
Date: Fri Jul 31 09:55:56 2020 +0200 Timestamp: 1596182156 Remove late irreversible move extension We simplify away the late irreversible move extension, which does not seem to be necessary in the current master. STC LLR: 2.93 (-2.94,2.94) {-1.50,0.50} Total: 38584 W: 7464 L: 7342 D: 23778 Elo +1.10 Ptnml(0-2): 581, 4328, 9365, 4424, 594 https://tests.stockfishchess.org/tests/view/5f1c9669c09435d870cb9de9 LTC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 27840 W: 3417 L: 3353 D: 21070 Elo +0.80 Ptnml(0-2): 120, 2315, 8994, 2363, 128 https://tests.stockfishchess.org/tests/view/5f1d2e22c09435d870cb9e21 closes https://github.com/official-stockfish/Stockfish/pull/2836 bench: 4829420 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: protonspring
Date: Fri Jul 31 09:47:24 2020 +0200 Timestamp: 1596181644 Remove conditional_more_than_two(). This is a functional simplification that removes the conditional_more_than_two() function, which was quite strange and kooky. Note the very minor change to the bench value. See this thread for relevant comments on the passing branch: protonspring/Stockfish@d89730d...ff35b50 STC LLR: 2.95 (-2.94,2.94) {-1.50,0.50} Total: 59760 W: 11411 L: 11311 D: 37038 Elo +0.58 Ptnml(0-2): 992, 6863, 14044, 7015, 966 https://tests.stockfishchess.org/tests/view/5f179988c09435d870cb9b9a LTC LLR: 2.93 (-2.94,2.94) {-1.50,0.50} Total: 45208 W: 5553 L: 5497 D: 34158 Elo +0.43 Ptnml(0-2): 315, 4081, 13761, 4127, 320 https://tests.stockfishchess.org/tests/view/5f184847c09435d870cb9bee closes https://github.com/official-stockfish/Stockfish/pull/2826 Bench: 4578290 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Vizvezdenec
Date: Fri Jul 17 20:28:44 2020 +0200 Timestamp: 1595010524 Do not overwrite valuable TT data after probcut. This patch allows an engine to write probcut data only in case the probcut search depth is greater than transposition table depth. passed STC https://tests.stockfishchess.org/tests/view/5f0b52e959f6f035328949a6 LLR: 2.97 (-2.94,2.94) {-0.50,1.50} Total: 52544 W: 10145 L: 9880 D: 32519 Elo +1.75 Ptnml(0-2): 853, 6097, 12121, 6334, 867 passed LTC https://tests.stockfishchess.org/tests/view/5f0bd94c59f6f035328949f3 LLR: 2.93 (-2.94,2.94) {0.25,1.75} Total: 49576 W: 6164 L: 5863 D: 37549 Elo +2.11 Ptnml(0-2): 297, 4371, 15218, 4538, 364 closes https://github.com/official-stockfish/Stockfish/pull/2815 bench 4578298 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: mstembera
Date: Fri Jul 17 20:24:02 2020 +0200 Timestamp: 1595010242 Multiple lazy stages. An extension of the lazy eval idea: when the score is sufficiently large we now skip more granular parts of the eval. Inspired by an original patch by Moez Jellouli https://tests.stockfishchess.org/tests/view/5f03b2a159f6f03532894529 Credit to him! STC https://tests.stockfishchess.org/tests/view/5f0a862c59f6f03532894924 LLR: 2.95 (-2.94,2.94) {-0.50,1.50} Total: 13504 W: 2684 L: 2472 D: 8348 Elo +5.45 Ptnml(0-2): 229, 1496, 3111, 1666, 250 LTC https://tests.stockfishchess.org/tests/view/5f0ac0e159f6f0353289495b LLR: 2.94 (-2.94,2.94) {0.25,1.75} Total: 31312 W: 3926 L: 3677 D: 23709 Elo +2.76 Ptnml(0-2): 185, 2773, 9509, 2986, 203 closes https://github.com/official-stockfish/Stockfish/pull/2814 bench: 4541608 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: syzygy1
Date: Sat Jul 11 22:32:34 2020 +0200 Timestamp: 1594499554 Corrects a functional change in a cleanup patch. This corrects a functional change in https://github.com/official-stockfish/Stockfish/commit/ddcbacd04d1c860e808202ce8c1206c8acdca627 changing evaluation of KPPvK. Bench remains unchanged at low depth With this patch, 8/8/5k1p/8/7p/7K/8/8 b - - 1 11 is again correctly evaluated as a draw. closes https://github.com/official-stockfish/Stockfish/pull/2807 Bench: 4366686 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: SFisGOD
Date: Sat Jul 11 11:23:55 2020 +0200 Timestamp: 1594459435 Introduce bad outpost penalty In some French games, Stockfish likes to bring the Knight to a bad outpost spot. This is evident in TCEC S18 Superfinal Game 63, where there is a Knight outpost on the queenside but is actually useless. Stockfish is effectively playing a piece down while holding ground against Leela's break on the kingside. This patch turns the +56 mg bonus for a Knight outpost into a -7 mg penalty if it satisfies the following conditions: * The outpost square is not on the CenterFiles (i.e. not on files C,D,E and F) * The knight is not attacking non pawn enemies. * The side where the outpost is located contains only few enemies, with a particular conditional_more_than_two() implementation Thank you to for bringing this to our attention and for providing insights. See https://groups.google.com/forum/?fromgroups=#!topic/fishcooking/dEXNzSIBgZU Reference game: https://tcec-chess.com/#div=sf&game=63&season=18 Passed STC: LLR: 2.93 (-2.94,2.94) {-0.50,1.50} Total: 6960 W: 1454 L: 1247 D: 4259 Elo +10.34 Ptnml(0-2): 115, 739, 1610, 856, 160 https://tests.stockfishchess.org/tests/view/5f08221059f6f0353289477e Passed LTC: LLR: 2.98 (-2.94,2.94) {0.25,1.75} Total: 21440 W: 2767 L: 2543 D: 16130 Elo +3.63 Ptnml(0-2): 122, 1904, 6462, 2092, 140 https://tests.stockfishchess.org/tests/view/5f0838ed59f6f035328947a2 various related tests show strong test results, but so far no generalizations or simplifications of conditional_more_than_two() are found. See PR for details. closes https://github.com/official-stockfish/Stockfish/pull/2803 Bench: 4366686 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Vizvezdenec
Date: Sat Jul 11 11:10:06 2020 +0200 Timestamp: 1594458606 Maximize usage of transposition table in probcut Probcut is a heuristic that wasn't changed a lot in past years, all attempts to change it using information / writing info to transposition table failed. This patch has a number of differences that can be summarized as follows: * For TT write/read we use depth - 3. Because probcut search is depth - 4 but we actually do the move prior to it so effectively we do depth - 3 search; * In any case of depth of eval from transposition table being >= depth - 3 we either produce cutoff or refuse to even do probcut search, this is allowing us to write info of probcut to transposition table because we know that we wouldn't be overwriting some deeper data with our depth - 3 search - this is an important aspect of this patch; * For some not really known reason this patch completely ignores tte->bound() - which was the case for previous patch that made probcut interact with TT, maybe 2) is the reason, although it's unproven. A first version of this patch passed STC and LTC passed STC https://tests.stockfishchess.org/tests/view/5f05908a59f6f03532894613 LLR: 2.95 (-2.94,2.94) {-0.50,1.50} Total: 95776 W: 18300 L: 17973 D: 59503 Elo +1.19 Ptnml(0-2): 1646, 10944, 22377, 11279, 1642 passed LTC https://tests.stockfishchess.org/tests/view/5f06b54059f6f035328946bb LLR: 2.94 (-2.94,2.94) {0.25,1.75} Total: 57128 W: 7266 L: 6938 D: 42924 Elo +1.99 Ptnml(0-2): 372, 5163, 17217, 5389, 423 However, an additional bugfix was needed to avoid checking a condition on ttMove if was not available. This passed non-regression bounds on top of the first version: at STC https://tests.stockfishchess.org/tests/view/5f080e5059f6f03532894766 LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 14096 W: 2800 L: 2628 D: 8668 Elo +4.24 Ptnml(0-2): 225, 1620, 3238, 1688, 277 at LTC https://tests.stockfishchess.org/tests/view/5f0836a559f6f0353289479c LLR: 2.95 (-2.94,2.94) {-1.50,0.50} Total: 25352 W: 3228 L: 3139 D: 18985 Elo +1.22 Ptnml(0-2): 175, 2350, 7549, 2415, 187 closes https://github.com/official-stockfish/Stockfish/pull/2804 Bench 4540940 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Joost VandeVondele
Date: Thu Jul 9 22:01:06 2020 +0200 Timestamp: 1594324866 Small cleanups closes https://github.com/official-stockfish/Stockfish/pull/2772 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: mstembera
Date: Thu Jul 9 21:59:32 2020 +0200 Timestamp: 1594324772 Simplify make_promotions() Remove special case handling of QUIET_CHECKS in make_promotions() STC https://tests.stockfishchess.org/tests/view/5f055dbb59f6f035328945fb LLR: 2.98 (-2.94,2.94) {-1.50,0.50} Total: 42808 W: 8177 L: 8054 D: 26577 Elo +1.00 Ptnml(0-2): 665, 4890, 10201, 4953, 695 LTC https://tests.stockfishchess.org/tests/view/5f06231a59f6f03532894661 LLR: 2.96 (-2.94,2.94) {-1.50,0.50} Total: 9616 W: 1214 L: 1111 D: 7291 Elo +3.72 Ptnml(0-2): 53, 821, 2965, 908, 61 closes https://github.com/official-stockfish/Stockfish/pull/2800 Bench: 4576410 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: FauziAkram
Date: Thu Jul 9 21:57:13 2020 +0200 Timestamp: 1594324633 Connected / blocked pawns simplification There is no need to score blocked pawns at many places. The idea originated from: Rocky Tuning and testing by: Fauzi Passed STC: https://tests.stockfishchess.org/tests/view/5f04f8fd59f6f035328945d4 LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 6352 W: 1299 L: 1118 D: 3935 Elo +9.90 Ptnml(0-2): 89, 695, 1469, 792, 131 Passed LTC: https://tests.stockfishchess.org/tests/view/5f0527bd59f6f035328945e3 LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 27648 W: 3517 L: 3433 D: 20698 Elo +1.06 Ptnml(0-2): 177, 2561, 8301, 2571, 214 closes https://github.com/official-stockfish/Stockfish/pull/2799 Bench: 4734746 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Alain SAVARD
Date: Thu Jul 9 21:46:26 2020 +0200 Timestamp: 1594323986 Clean-up en passant processing the goal of this PR is to better document how we process the ep square (if any) given position fen command, and to output more meaningful (and consistent) debug fen on the "d" command. The implementation follows https://en.wikipedia.org/wiki/X-FEN#Encoding_en-passant following x-fen, it is "valid" to record ep even if ep would put king en prise. fixes #2784 closes https://github.com/official-stockfish/Stockfish/pull/2797 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stefan Geschwentner
Date: Mon Jul 6 17:56:18 2020 +0200 Timestamp: 1594050978 Add a rank based bonus for blocked pawns. Fix for overevaluated blocked pawns on the 5th and 6th rank. This is a rewrite of the original idea that uses only two parameters. Thanks to rocky640 for pointing this out. STC: LLR: 2.94 (-2.94,2.94) {-0.50,1.50} Total: 50800 W: 9707 L: 9446 D: 31647 Elo +1.79 Ptnml(0-2): 831, 5851, 11822, 6018, 878 https://tests.stockfishchess.org/tests/view/5f00b4f359f6f03532894304 LTC: LLR: 2.93 (-2.94,2.94) {0.25,1.75} Total: 52064 W: 6477 L: 6167 D: 39420 Elo +2.07 Ptnml(0-2): 331, 4628, 15834, 4878, 361 https://tests.stockfishchess.org/tests/view/5f0115fe59f6f03532894345 closes https://github.com/official-stockfish/Stockfish/pull/2794 Bench: 4882833 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: protonspring
Date: Mon Jul 6 17:50:35 2020 +0200 Timestamp: 1594050635 denormalize KRKP. a non-functional code style change that denormalizes the KRKP endgame, making it somewhat easier to read. closes https://github.com/official-stockfish/Stockfish/pull/2786 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: SFisGOD
Date: Fri Jul 3 21:09:22 2020 +0200 Timestamp: 1593803362 Remove passed pawn condition. This will help scale down relatively high eval in drawish rook endgames with passed pawn like in TCEC S18 Superfinal Game 90. Passed STC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 50456 W: 9644 L: 9540 D: 31272 Elo +0.72 Ptnml(0-2): 760, 5637, 12332, 5737, 762 https://tests.stockfishchess.org/tests/view/5efcb76e59f6f035328940ed Passed LTC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 77264 W: 9518 L: 9518 D: 58228 Elo +0.00 Ptnml(0-2): 402, 6766, 24321, 6716, 427 https://tests.stockfishchess.org/tests/view/5efd2ad759f6f03532894143 closes https://github.com/official-stockfish/Stockfish/pull/2792 Bench: 4431626 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Joost VandeVondele
Date: Fri Jul 3 21:07:17 2020 +0200 Timestamp: 1593803237 Set UCI_ShowWDL by default to false UCI_ShowWDL might not be shown by GUIs that don't know the option, but crash on the WDL output, effectively making it hard for users to turn it off and run the engine. This sets it by default to false. fixes https://github.com/official-stockfish/Stockfish/issues/2787 closes https://github.com/official-stockfish/Stockfish/pull/2788 No functional change. see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Alain SAVARD
Date: Fri Jul 3 21:06:36 2020 +0200 Timestamp: 1593803196 Use arrays for safe checks, outposts and king protectors in evaluate.cpp Tested for non regression on the safe checks https://tests.stockfishchess.org/tests/view/5ef8b75c020eec13834a9596 LLR: 2.95 (-2.94,2.94) {-1.50,0.50} Total: 22256 W: 4283 L: 4143 D: 13830 Elo +2.19 Ptnml(0-2): 291, 2439, 5588, 2459, 351 Tested for non regression on the safe checks, outposts and king protectors https://tests.stockfishchess.org/tests/view/5ef8e543020eec13834a95e7 LLR: 2.95 (-2.94,2.94) {-1.50,0.50} Total: 28400 W: 5382 L: 5253 D: 17765 Elo +1.58 Ptnml(0-2): 394, 3078, 7119, 3223, 386 closes https://github.com/official-stockfish/Stockfish/pull/2785 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Joost VandeVondele
Date: Wed Jul 1 07:33:05 2020 +0200 Timestamp: 1593581585 Provide WDL statistics A number of engines, GUIs and tournaments start to report WDL estimates along or instead of scores. This patch enables reporting of those stats in a more or less standard way (http://www.talkchess.com/forum3/viewtopic.php?t=72140) The model this reporting uses is based on data derived from a few million fishtest LTC games, given a score and a game ply, a win rate is provided that matches rather closely, especially in the intermediate range [0.05, 0.95] that data. Some data is shown at https://github.com/glinscott/fishtest/wiki/UsefulData#win-loss-draw-statistics-of-ltc-games-on-fishtest Making the conversion game ply dependent is important for a good fit, and is in line with experience that a +1 score in the early midgame is more likely a win than in the late endgame. Even when enabled, the printing of the info causes no significant overhead. Passed STC: LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 197112 W: 37226 L: 37347 D: 122539 Elo -0.21 Ptnml(0-2): 2591, 21025, 51464, 20866, 2610 https://tests.stockfishchess.org/tests/view/5ef79ef4f993893290cc146b closes https://github.com/official-stockfish/Stockfish/pull/2778 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stefan Geschwentner
Date: Mon Jun 29 20:02:58 2020 +0200 Timestamp: 1593453778 Tweak single queen endgame scaling. Increase scaling factor for each minor of the opponent side of the queen. STC: LLR: 2.94 (-2.94,2.94) {-0.50,1.50} Total: 14528 W: 2860 L: 2653 D: 9015 Elo +4.95 Ptnml(0-2): 217, 1632, 3408, 1741, 266 https://tests.stockfishchess.org/tests/view/5ef98384020eec13834a96a0 LTC: LLR: 2.95 (-2.94,2.94) {0.25,1.75} Total: 34584 W: 4371 L: 4111 D: 26102 Elo +2.61 Ptnml(0-2): 205, 3080, 10501, 3262, 244 https://tests.stockfishchess.org/tests/view/5ef99972020eec13834a96c9 closes https://github.com/official-stockfish/Stockfish/pull/2782 Bench: 4523573 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stéphane Nicolet
Date: Sun Jun 28 22:42:43 2020 +0200 Timestamp: 1593376963 Scale down eval for queen imbalance We lower the endgame value of the evaluation when we detect that there is only one queen left on the board (more precisely, we use a scale factor of 37/64, or about 0.58, for the endgame part of the evaluation). Hopefully this helps a little bit for the assessment of positions with queen imbalance, which are one of the well-known Stockfish weaknesses. STC: LLR: 2.94 (-2.94,2.94) {-0.50,1.50} Total: 21600 W: 4176 L: 3955 D: 13469 Elo +3.55 Ptnml(0-2): 351, 2457, 5003, 2598, 391 https://tests.stockfishchess.org/tests/view/5ef871b6020eec13834a94e8 LTC: LLR: 2.97 (-2.94,2.94) {0.25,1.75} Total: 248328 W: 30596 L: 29720 D: 188012 Elo +1.23 Ptnml(0-2): 1544, 22345, 75665, 22911, 1699 https://tests.stockfishchess.org/tests/view/5ef87aec020eec13834a94fe Closes https://github.com/official-stockfish/Stockfish/pull/2781 Bench: 4441323 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stefan Geschwentner
Date: Sun Jun 28 22:05:09 2020 +0200 Timestamp: 1593374709 Scale down eval for drawish rook endgames. STC: LLR: 2.96 (-2.94,2.94) {-0.50,1.50} Total: 82136 W: 15694 L: 15407 D: 51035 Elo +1.21 Ptnml(0-2): 1076, 8960, 20767, 9131, 1134 https://tests.stockfishchess.org/tests/view/5ef86cf8020eec13834a94dd LTC: LLR: 2.93 (-2.94,2.94) {0.25,1.75} Total: 70200 W: 8787 L: 8440 D: 52973 Elo +1.72 Ptnml(0-2): 325, 5983, 22170, 6264, 358 https://tests.stockfishchess.org/tests/view/5ef88225020eec13834a950a closes https://github.com/official-stockfish/Stockfish/pull/2780 Bench: 4478869 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: Stéphane Nicolet
Date: Sun Jun 28 22:03:10 2020 +0200 Timestamp: 1593374590 Increase value of pawns on fifth rank This patch increases the endgame value of pawns on the fifth rank. The increase is very small (+1 evaluation point, about 0.005 pawn) for the pawns on external columns (a-b-c-f-g-h) and a bit bigger (+7 evaluation points, about 0.033 pawn) for the pawns on d5/e5. STC: LLR: 2.93 (-2.94,2.94) {-0.50,1.50} Total: 79864 W: 15331 L: 15027 D: 49506 Elo +1.32 Ptnml(0-2): 1336, 9284, 18433, 9498, 1381 https://tests.stockfishchess.org/tests/view/5ef73e2ef993893290cc0c47 LTC: LLR: 2.94 (-2.94,2.94) {0.25,1.75} Total: 47240 W: 5927 L: 5630 D: 35683 Elo +2.18 Ptnml(0-2): 320, 4133, 14440, 4384, 343 https://tests.stockfishchess.org/tests/view/5ef7c0c4f993893290cc14b7 closes https://github.com/official-stockfish/Stockfish/pull/2776 Bench: 4794633 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 Windows 32 Linux x64 for Haswell CPUs Linux x64 for modern computers Linux x64 | Author: mstembera
Date: Sun Jun 28 22:00:19 2020 +0200 Timestamp: 1593374419 Remove old zobrist trick for castling rights Removes an 8 year old micro optimization aimed at 32-bit architectures because back then doing an xor of a Key could not be done in one instruction. See original commit here 821e1c7 STC https://tests.stockfishchess.org/tests/view/5ef5833dde213bf647527d0c LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 162648 W: 31053 L: 31097 D: 100498 Elo -0.09 Ptnml(0-2): 2841, 18966, 37715, 19000, 2802 LTC https://tests.stockfishchess.org/tests/view/5ef7b1bbf993893290cc1489 LLR: 2.93 (-2.94,2.94) {-1.50,0.50} Total: 62360 W: 7617 L: 7586 D: 47157 Elo +0.17 Ptnml(0-2): 423, 5662, 18994, 5663, 438 closes https://github.com/official-stockfish/Stockfish/pull/2775 bench: 4591425 see source |