diff --git a/src/search.cpp b/src/search.cpp index 1bf855d5589..7c9c1b6936b 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -995,7 +995,14 @@ namespace { Depth r = reduction(improving, depth, moveCount); if (captureOrPromotion) // (~5 Elo) + { + //Increase reduction by comparing opponent's stat score + if ( (ss-1)->statScore >= 0 + && thisThread->captureHistory[movedPiece][to_sq(move)][type_of(pos.captured_piece())] < 0) + r += ONE_PLY; + r -= r ? ONE_PLY : DEPTH_ZERO; + } else { // Decrease reduction if opponent's move count is high (~5 Elo)