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Official Stockfish pre-release: Stockfish dev-20240917-60351b9d



Official Stockfish dev-20240917-60351b9d Pre-release
RatingChess Engines Diary CEDR=3783
Stockfish dev-20240917-60351b9d Pre-release download


Stockfish dev-20240917-60351b9d Pre-release
Introduce Various Correction histories

This patch introduces three additional correction histories, namely, Major Piece Correction History, Minor Piece Correction History, and Non-Pawn Correction History.

Introduced by @mcthouacbb in Sirius
(https://github.com/mcthouacbb/Sirius) chess engine. The Major Piece Correction History is indexed by side-to-move and the Zobrist key representing the position of the King, Rook, and Queen of both sides.
Likewise, the Minor Piece Correction History is indexed by side-to-move and the Zobrist key representing the position of the King, Knight, and Bishop of both sides.

Also See:
https://github.com/mcthouacbb/Sirius/commit/97b85bbaac88ff5a0f63e28776027dd3de77164e
https://github.com/mcthouacbb/Sirius/commit/3099cdef2f13e29805654b5f8153e6ecd5853195

Introduced by @zzzzz151 in Starzix (https://github.com/zzzzz151/Starzix) chess engine. Non-Pawn correction history consists of side-to-move, side of Zobrist key, and a Zobrist key representing of the position of all non-pawn pieces of **one side**. The non-pawn correction values for both key sides are then summed.

Also See:
https://github.com/zzzzz151/Starzix/commit/34911772f178c27b3a239dda0acb79c397c3a2f0
https://github.com/zzzzz151/Starzix/commit/33e0df8dd2db1d4775974ab12e3390154697f47a

The weights on the final correction value of the above correction histories, as well as existing correction histories, are then tuned in two separate SPSA sessions, totaling 75k games.

SPSA1:
https://tests.stockfishchess.org/tests/view/66e5243886d5ee47d953a86b
(Stopped early due to some weights reaching the maximum value)

SPSA2:
https://tests.stockfishchess.org/tests/view/66e6a26f86d5ee47d953a965

Also thanks to @martinnovaak, (Motor
https://github.com/martinnovaak/motor author) for insights and suggestions.

Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 23328 W: 6197 L: 5901 D: 11230
Ptnml(0-2): 82, 2582, 6041, 2876, 83
https://tests.stockfishchess.org/tests/view/66e8787b86d5ee47d953ab6f

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 10626 W: 2826 L: 2560 D: 5240
Ptnml(0-2): 4, 1054, 2941, 1300, 14
https://tests.stockfishchess.org/tests/view/66e8ab2386d5ee47d953aba8

closes https://github.com/official-stockfish/Stockfish/pull/5598

Bench: 1011161



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