Run T-0142 passed

2026-09-29 · Evidence: SPRT Sequential probability ratio test. Games are played until the accumulated evidence reaches one of two bounds; then the test stops.

Hypothesis

If negamax prunes late, non-checking quiet moves before make_move whenever their computed LMR reduction r satisfies r > 0 and depth - r <= FutilityMaxDepth, provided original_alpha is outside the mate range, pruning_eval + FutilityMargin * (depth - r) <= original_alpha, and the side to move has non-pawn material, the engine will gain playing strength. All other LMR reductions and the existing node-level futility pruning up to depth 2 remain unchanged.

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

Stages

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	long stage
Verdict	passed	passed
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.	+6.56 ± 4.35	+7.12 ± 4.46
nElo Normalised Elo: the Elo difference divided by the spread of the game results, so that the SPRT bounds mean the same at different time controls.	+11.66 ± 7.72	+13.45 ± 8.42
Games	7,782	6,542
Wins / draws / losses	1,974 / 3,981 / 1,827	1,553 / 3,570 / 1,419
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.	`70 / 856 / 1918 / 951 / 96`	`18 / 755 / 1615 / 841 / 42`
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	+2.97
Bounds	−2.94 … +2.94	−2.94 … +2.94
SPRT Sequential probability ratio test. Games are played until the accumulated evidence reaches one of two bounds; then the test stops.	[0.0, 5.0]	[0.0, 5.0]
Error rates α / β	0.05 / 0.05	0.05 / 0.05
Model	normalized	normalized
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	40+0.4
Book	A	B
Opponent	vs predecessor	vs predecessor
Duration	1 h 01 min	4 h 28 min

Provenance

Date: 2026-09-29
Started: 2026-09-29 13:28:41 UTC
Duration: 5 h 29 min
Author: Agent X
Epoch: 6
Gatekeeper: passed
Bench nodes: 3,955

Playing strength carried forward

3479 ± 53

An estimate, not a measured Elo. This build has not played a single listed opponent — anchored is 0.1.118 alone, and this figure is carried on from there. The chain is measured against our own predecessors, at a different time control and a different book, and an SPRT that stops at its upper bound reports a gain that is biased upward. The figure is therefore more likely too high than too low. Only the anchoring itself is a measurement.

How it is worked out

The anchoring measures Coherent 0.1.118, the build of run T-0135: 3455 ± 52, transferred over foreign engines with a published rating at 120+1.
The register carries the passed long stages after T-0135: +6.82 (T-0138) +10.32 (T-0141) +7.12 (T-0142), together +24.26, each measured against its own predecessor at 40+0.4.
3455, plus +24.26, gives 3479. The half-widths are combined in quadrature — the root of the sum of the squares: ± 52 and ± 8.30 make ± 53.