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Add extra bonus to pawn history for a move that caused a fail low. #5243

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Vizvezdenec
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Basically the same idea as it is for continuation/main history, but it has some tweaks.

  1. it has * 2 multiplier for bonus instead of full/half bonus - for whatever reason this seems to work better;
  2. attempts with this type of big bonuses scaled somewhat poorly (or were unlucky at longer time controls), but after measuring the fact that average value of pawn history in LMR after adding this bonuses increased by substantial number (for multiplier 1,5 it increased by smth like 400~ from 8192 cap) attempts were made to make default pawn history negative to compensate it - and version with multiplier 2 and initial fill value -900 passed.
    Passed STC:
    https://tests.stockfishchess.org/tests/view/66424815f9f4e8fc783cba59
    LLR: 2.93 (-2.94,2.94) <0.00,2.00>
    Total: 115008 W: 30001 L: 29564 D: 55443
    Ptnml(0-2): 432, 13629, 28903, 14150, 390
    Passed LTC:
    https://tests.stockfishchess.org/tests/view/6642f5437134c82f3f7a3ffa
    LLR: 2.94 (-2.94,2.94) <0.50,2.50>
    Total: 56448 W: 14432 L: 14067 D: 27949
    Ptnml(0-2): 36, 6268, 15254, 6627, 39
    bench 1725439

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clang-format 17 needs to be run on this PR.
If you do not have clang-format installed, the maintainer will run it when merging.
For the exact version please see https://packages.ubuntu.com/mantic/clang-format-17.

(execution 9083444064 / attempt 1)

@Disservin Disservin added 🚀 gainer Gains elo functional-change to be merged Will be merged shortly labels May 15, 2024
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merged with 9e45644

@Disservin Disservin closed this May 15, 2024
vondele pushed a commit to vondele/Stockfish that referenced this pull request Jul 3, 2024
This patch introduces history updates to probcut. Standard depth - 3 bonus and
maluses are given to the capture that caused fail high and previously searched
captures, respectively. Similar to official-stockfish#5243, a negative history fill is applied to
compensate for an increase in capture history average, thus improving the
scaling of this patch.

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 84832 W: 21941 L: 21556 D: 41335
Ptnml(0-2): 226, 9927, 21688, 10386, 189
https://tests.stockfishchess.org/tests/view/6682fab9389b9ee542b1d029

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 104298 W: 26469 L: 26011 D: 51818
Ptnml(0-2): 43, 11458, 28677, 11940, 31
https://tests.stockfishchess.org/tests/view/6682ff06389b9ee542b1d0a0

closes official-stockfish#5428

bench 1281351
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