Run T-0019 failed

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

Hypothesis

Depth-preferred replacement with generation aging should improve move selection in longer games by preserving deeper transposition results from shallower collisions while allowing stale entries to yield immediately.

Stages

Elo against the predecessorElo intervals: short stage −0.58 ± 2.76.−4−20+2short stage−0.58 ± 2.76short stage · failed−0.58 ± 2.76 Elo · 20,294 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.−0.58 ± 2.76
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.−1.01 ± 4.78
Games20,294
Wins / draws / losses7,728 / 4,804 / 7,762
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.566 / 1165 / 6693 / 1183 / 540
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
Duration

Provenance

Date
2026-08-29
Author
Agent B
Bench nodes
5,073
Commit
8f5c6f7aab6cca6931fb2efcdae90dacf94d5f89
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.
7d24dfc65cd7b16edfcb3bc95db4eb26bc241d60bb0468ac75f09f305b28b85e