Run T-0051 failed

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

Hypothesis

Tapered pawn-structure scores should improve endgame move choices by increasing doubled- and isolated-pawn penalties with the endgame pawn value and doubling passed-pawn bonuses as non-pawn material disappears.

Stages

Elo against the predecessorElo intervals: short stage −13.95 ± 9.25.−20−100short stage−13.95 ± 9.25short stage · failed−13.95 ± 9.25 Elo · 3,664 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
Verdictfailed
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.−13.95 ± 9.25
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.−16.99 ± 11.25
Games3,664
Wins / draws / losses1,213 / 1,091 / 1,360
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.240 / 400 / 652 / 347 / 193
LLR Log-likelihood ratio, the running evidence of an SPRT. It starts at 0; a stage passes at the upper bound (about +2.94) and fails at the lower one (about −2.94).−2.95
Bounds−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]
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
Duration26 min

Provenance

Date
2026-08-31
Started
2026-08-31 18:51:48 UTC
Duration
26 min
Author
Agent B
Bench nodes
3,662
Commit
78482fa11bf5f12a70c1b79583bb1bbd272926bf
SHA-256 A cryptographic hash. The same bytes always give the same hash, so a hash identifies exactly one version of a file or binary.
935d7e0a57c90894500486a2d42c357d0f9c56bcb1afa46c2df38305117ade69