Latest abrok Development Version September 17 th (SF The gift that keeps on giving

!! latest version !!

Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64

Author: mstembera
Date: Sat Sep 17 09:30:52 2022 +0200
Timestamp: 1663399852

Prioritize checks in movepicker

give a little bonus for moving pieces to squares where they give check

STC: https://tests.stockfishchess.org/tests/view/631da742162491686d2e40b5
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 80072 W: 21753 L: 21368 D: 36951 Elo +1.67
Ptnml(0-2): 421, 8876, 21075, 9225, 439

LTC: https://tests.stockfishchess.org/tests/view/631dd9e6b85daa436625de1d
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 263480 W: 70916 L: 70158 D: 122406 Elo +1.00
Ptnml(0-2): 322, 26156, 78029, 26908, 325

similar ideas have been tested by Viz and Guenther

closes https://github.com/official-stockfish/Stockfish/pull/4165

bench: 4326572
see source

Windows x64 for Haswell CPUs
Windows x64 for modern computers + AVX2
Windows x64 for modern computers
Windows x64 + SSSE3
Windows x64
Linux x64 for Haswell CPUs
Linux x64 for modern computers + AVX2
Linux x64 for modern computers
Linux x64 + SSSE3
Linux x64

Author: atumanian
Date: Sat Sep 17 09:13:07 2022 +0200
Timestamp: 1663398787

Simplify trend and optimism.

This patch simplifies the formulas used to compute the trend and optimism values before each search iteration.
As a side effect, this removes the parameters which make the relationship between the displayed evaluation value
and the expected game result asymmetric.

I've also provided links to the results of isotonic regression analysis of the relationship between the evaluation and game result (statistical data and a graph) for both tests, which demonstrate that the new version has a more symmetric relationship:

STC: [Data and graph](https://github.com/official-stockfish/Stockfish/discussions/4150#discussioncomment-3548954)
LTC: [Data and graph](https://github.com/official-stockfish/Stockfish/discussions/4150#discussioncomment-3626311)
See also https://github.com/official-stockfish/Stockfish/issues/4142

passed STC:
https://tests.stockfishchess.org/tests/view/6313f44b8202a039920e27e6
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 108016 W: 28903 L: 28760 D: 50353 Elo +0.46
Ptnml(0-2): 461, 12075, 28850, 12104, 518

passed LTC:
https://tests.stockfishchess.org/tests/view/631de45db85daa436625dfe6
LLR: 3.01 (-2.94,2.94) <-1.75,0.25>
Total: 34792 W: 9412 L: 9209 D: 16171 Elo +2.03
Ptnml(0-2): 24, 3374, 10397, 3577, 24

Furthermore, this does not measurably impact Elo strength against weaker engines,
as demonstrated in a match of master and patch vs SF13:

This patch vs SF 13:
https://tests.stockfishchess.org/tests/view/631fa34ae1612778c344c6eb
Elo: 141.66 +-1.2 (95%) LOS: 100.0%
Total: 100000 W: 48182 L: 9528 D: 42290 Elo +141.66
Ptnml(0-2): 96, 1426, 13277, 30130, 5071
nElo: 284.13 +-3.3 (95%) PairsRatio: 23.13

Master vs SF 13:
https://tests.stockfishchess.org/tests/view/631fa3ece1612778c344c6ff
Elo: 143.26 +-1.2 (95%) LOS: 100.0%
Total: 100000 W: 48525 L: 9479 D: 41996 Elo +143.26
Ptnml(0-2): 94, 1537, 13098, 29771, 5500
nElo: 281.70 +-3.3 (95%) PairsRatio: 21.63

closes: https://github.com/official-stockfish/Stockfish/pull/4163

Bench: 4425574
see source

_________________
Bettina...............The greatest happiness of life is the conviction that we are loved.

Victor Hugo

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