// 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]));
// 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;