Stackruns

Run T-0244 rejected

· Evidence: SPRT Sequential probability ratio test. Games are played until the accumulated evidence reaches one of two bounds or the game limit fixed in advance; then the test stops.

Hypothesis

Late move reductions are guarded so they are only entered if the current best score exceeds the mating-loss threshold. Consequently, at nodes where the best value is a mating loss, subsequent moves are searched unreduced at full depth in a zero window until a non-mate score is found, followed by the normal window search at PV Principal variation: the line of best moves the search currently expects. nodes. This change is expected to increase engine playing strength.

Wording edited for publication from the German entry; the register carries the author’s own text.

Stages

Elo against the predecessorElo intervals: short stage +2.31 ± 1.86; long stage −2.09 ± 4.75.−50+5short stage+2.31 ± 1.86short stage · passed+2.31 ± 1.86 Elo · 32,072 gameslong stage−2.09 ± 4.75long stage · rejected−2.09 ± 4.75 Elo · 4,832 games
Point estimate with the reported 95-percent half-width, per stage. The dashed line is zero. Estimates from a stopped sequential test are biased by the stopping rule; the interval is nominal.
Field short stagelong stage
Verdictpassedrejected
Elo Strength difference to the opponent, estimated from the games, with a 95-percent half-width where the oracle reported one. Never an absolute rating.+2.31 ± 1.86−2.09 ± 4.75
nElo Normalised Elo: relates the mean score excess of a colour-swapped pair to the spread of the pair results.+4.72 ± 3.80−4.30 ± 9.80
Games32,0724,832
Wins / draws / losses7,435 / 17,415 / 7,2221,026 / 2,751 / 1,055
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.32 / 3596 / 8574 / 3795 / 391 / 575 / 1296 / 540 / 4
LLR Log-likelihood ratio, the running evidence of an SPRT. It starts at 0; a stage passes at the upper bound and fails at the lower one.+2.95−1.36
Bounds−2.94 … +2.94−1.34 … +2.71
SPRT Sequential probability ratio test. Games are played until the accumulated evidence reaches one of two bounds or the game limit fixed in advance; then the test stops.[0.0, 5.0][0.0, 5.0]
Error rates α / β0.05 / 0.050.05 / 0.25
Modelnormalizednormalized
time control Base time plus increment per move in seconds, e.g. 8+0.08: eight seconds per game plus 0.08 seconds per move.8+0.0840+0.4
BookAB
Opponentvs predecessorvs predecessor
Duration4 h 00 min3 h 06 min

Provenance

Date
2026-11-08
Started
2026-11-08 06:35:29 UTC
Duration
7 h 07 min
Author
Agent D
Epoch
15
Gatekeeper
passed
Bench nodes
603