From 341163116233682bf150d20cddedcb23e6d09431 Mon Sep 17 00:00:00 2001 From: Joost VandeVondele Date: Sat, 19 Nov 2022 13:03:14 +0100 Subject: [PATCH] Update WDL model for current SF This updates the WDL model based on the LTC statistics (2M games). Relatively small change, note that this also adjusts the NormalizeToPawnValue (now 361), to keep win prob at 50% for 100cp. closes https://github.com/official-stockfish/Stockfish/pull/4236 No functional change. --- src/uci.cpp | 4 ++-- src/uci.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/src/uci.cpp b/src/uci.cpp index 19e2b0cb..5d842d25 100644 --- a/src/uci.cpp +++ b/src/uci.cpp @@ -207,8 +207,8 @@ namespace { // The coefficients of a third-order polynomial fit is based on the fishtest data // for two parameters that need to transform eval to the argument of a logistic // function. - constexpr double as[] = { 1.04790516, -8.58534089, 39.42615625, 316.17524816}; - constexpr double bs[] = { -3.57324784, 22.28816201, -35.47480551, 85.60617701 }; + constexpr double as[] = { -0.58270499, 2.68512549, 15.24638015, 344.49745382}; + constexpr double bs[] = { -2.65734562, 15.96509799, -20.69040836, 73.61029937 }; // Enforce that NormalizeToPawnValue corresponds to a 50% win rate at ply 64 static_assert(UCI::NormalizeToPawnValue == int(as[0] + as[1] + as[2] + as[3])); diff --git a/src/uci.h b/src/uci.h index f5f2c385..7a2ef255 100644 --- a/src/uci.h +++ b/src/uci.h @@ -35,7 +35,7 @@ namespace UCI { // the win_rate_model() such that Stockfish outputs an advantage of // "100 centipawns" for a position if the engine has a 50% probability to win // from this position in selfplay at fishtest LTC time control. -const int NormalizeToPawnValue = 348; +const int NormalizeToPawnValue = 361; class Option; -- 2.39.2