🔍 Fail soft TT cutoffs

[eduherminio]

Failed implementations

Test  | search/fail-soft-TT
Elo   | -179.79 +- 23.92 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | -2.28 (-2.25, 2.89) [0.00, 3.00]
Games | 536: +51 -306 =179
Penta | [80, 108, 67, 13, 0]
https://openbench.lynx-chess.com/test/758/

Depends on #1041 maybe?

Nope

Score of Lynx-search-fail-soft-tt-4032-win-x64 vs Lynx 4031 - main: 36 - 193 - 94  [0.257] 323
...      Lynx-search-fail-soft-tt-4032-win-x64 playing White: 31 - 75 - 55  [0.363] 161
...      Lynx-search-fail-soft-tt-4032-win-x64 playing Black: 5 - 118 - 39  [0.151] 162
...      White vs Black: 149 - 80 - 94  [0.607] 323
Elo difference: -184.5 +/- 34.2, LOS: 0.0 %, DrawRatio: 29.1 %
SPRT: llr -2.26 (-78.3%), lbound -2.25, ubound 2.89 - H0 was accepted

Maybe #1046?

Nope

Test  | search/fail-soft-TT-test-with-qsearch-failsoft
Elo   | -279.59 +- 920.24 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | -0.06 (-2.25, 2.89) [0.00, 3.00]
Games | 12: +0 -8 =4
Penta | [4, 0, 2, 0, 0]
https://openbench.lynx-chess.com/test/765/

Reverting TT raw score usage:

8+0.08

Score of Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 vs Lynx 4045 - main: 1294 - 1099 - 2180  [0.521] 4573
...      Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 playing White: 998 - 233 - 1056  [0.667] 2287
...      Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 playing Black: 296 - 866 - 1124  [0.375] 2286
...      White vs Black: 1864 - 529 - 2180  [0.646] 4573
Elo difference: 14.8 +/- 7.3, LOS: 100.0 %, DrawRatio: 47.7 %
SPRT: llr 2.9 (100.3%), lbound -2.25, ubound 2.89 - H1 was accepted

40+0.4 (stopped)

Score of Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 vs Lynx 4045 - main: 297 - 274 - 549  [0.510] 1120
...      Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 playing White: 250 - 53 - 257  [0.676] 560
...      Lynx-search-fail-soft-tt-revert-rawscore-4049-win-x64 playing Black: 47 - 221 - 292  [0.345] 560
...      White vs Black: 471 - 100 - 549  [0.666] 1120
Elo difference: 7.1 +/- 14.5, LOS: 83.2 %, DrawRatio: 49.0 %
SPRT: llr 0.308 (10.6%), lbound -2.25, ubound 2.89