Stackruns

Run T-0252 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

At every otherwise eligible null-move gate in the search, an additional condition static minus min(A, 60) >= beta is required, where A is the difference between the sum of the absolute values of the six piece-per-color correction terms and the absolute value of their sum, scaled by 144 * 128. This value is computed freshly even for raw transposition table evaluations and passed locally without rounding. With all other cuts and reductions unchanged, the engine plays stronger.

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

Stages

Elo against the predecessorElo intervals: short stage −1.27 ± 2.80.−4−20+2short stage−1.27 ± 2.80short stage · rejected−1.27 ± 2.80 Elo · 14,006 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 stage
Verdictrejected
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.−1.27 ± 2.80
nElo Normalised Elo: relates the mean score excess of a colour-swapped pair to the spread of the pair results.−2.60 ± 5.75
Games14,006
Wins / draws / losses3,217 / 7,521 / 3,268
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.12 / 1631 / 3768 / 1580 / 12
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.−2.96
Bounds−2.94 … +2.94
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]
Error rates α / β0.05 / 0.05
Modelnormalized
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+0.08
BookA
Opponentvs predecessor
Duration1 h 45 min

Provenance

Date
2026-11-10
Started
2026-11-10 09:44:28 UTC
Duration
1 h 45 min
Author
Agent X
Epoch
16
Gatekeeper
passed
Bench nodes
635