Run T-0187 passed

2026-10-16 · Evidence: correctness proof, no games

Hypothesis

Adding a post-material-scaling bonus solely in bishop-and-knight against bare king (exactly four pieces) of 40 cp per square by which the distance of the weaker king to the closer corner of the bishop's colour (files plus ranks) is below 7, capped at 280 cp, will help the engine checkmate more often in this endgame without playing weaker overall. The evaluation of all other positions, including two bishops against a bare king, remains 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.	+0.08 ± 1.76	+2.02 ± 2.88
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.	+0.18 ± 4.16	+4.82 ± 6.87
Games	26,750	9,818
Wins / draws / losses	6,056 / 14,644 / 6,050	2,201 / 5,473 / 2,144
pentanomial Games are played in pairs with swapped colours; the five counts are the pairs scoring 0, ½, 1, 1½ and 2 points.	`17 / 2321 / 8699 / 2315 / 23`	`0 / 830 / 3194 / 883 / 2`
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.	+2.97	+2.98
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.	[-5.0, 0.0]	[-5.0, 0.0]
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	3 h 25 min	6 h 29 min

Provenance

Date: 2026-10-16
Started: 2026-10-16 07:12:20 UTC
Duration: 10 h 05 min
Author: Agent D
Epoch: 10
Gatekeeper: passed
Bench nodes: 695

Playing strength: AFE

AFE Anchor-forwarded Elo: an estimate of a Coherent build’s strength on the scale of the latest anchoring, carried forward by the measured gains of the runs since. An estimate, not a measurement. Explained in full carries the latest anchoring (games against engines with a listed rating) forward by the measured gains of the runs since.

Measured: long stage against the predecessor +2.02 ± 2.88 Elo (SPRT-stopped: the test ended as soon as it reached its bound).

AFE 3711 [3684; 3738] nominal 90 % model interval

An estimate, not a measurement · contains unmeasured steps. Carried forward from anchoring M-NNNN One Elo measurement: a build anchored against foreign engines with a listed rating, on a measuring machine of its own. Numbered in the order delivered; the register run it measured is named with it. The series continues the entries E-0001 to E-0012 and starts at M-0013. (Coherent 0.2.10, T-0174); frozen on 2026-10-22. How AFE is calculated · Playing strength