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NCM plays each Stockfish dev build 20,000 times against Stockfish 14. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds.


Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo

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ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN


Commit ID e8d64af1230fdac65bb0da246df3e7abe82e0838
Author Tomasz Sobczyk
Date 2021-05-18 16:06:23 UTC
New NNUE architecture and net Introduces a new NNUE network architecture and associated network parameters, as obtained by a new pytorch trainer. The network is already very strong at short TC, without regression at longer TC, and has potential for further improvements. TC: 10s+0.1s, 1 thread ELO: 21.74 +-3.4 (95%) LOS: 100.0% Total: 10000 W: 1559 L: 934 D: 7507 Ptnml(0-2): 38, 701, 2972, 1176, 113 TC: 60s+0.6s, 1 thread ELO: 5.85 +-1.7 (95%) LOS: 100.0% Total: 20000 W: 1381 L: 1044 D: 17575 Ptnml(0-2): 27, 885, 7864, 1172, 52 TC: 20s+0.2s, 8 threads LLR: 2.93 (-2.94,2.94) <0.50,3.50> Total: 34272 W: 1610 L: 1452 D: 31210 Ptnml(0-2): 30, 1285, 14350, 1439, 32 TC: 60s+0.6s, 8 threads LLR: 2.94 (-2.94,2.94) <-2.50,0.50> Total: 45544 W: 1262 L: 1214 D: 43068 Ptnml(0-2): 12, 1129, 20442, 1177, 12 The network has been trained (by vondele) using the trainer (started by glinscott), specifically the branch The data used are in 64 billion positions (193GB total) generated and scored with the current master net d8: d9: d10: fishtest_d9: This network also contains a few architectural changes with respect to the current master: Size changed from 256x2-32-32-1 to 512x2-16-32-1 ~15-20% slower ~2x larger adds a special path for 16 valued ClippedReLU fixes affine transform code for 16 inputs/outputs, buy using InputDimensions instead of PaddedInputDimensions this is safe now because the inputs are processed in groups of 4 in the current affine transform code The feature set changed from HalfKP to HalfKAv2 Includes information about the kings like HalfKA Packs king features better, resulting in 8% size reduction compared to HalfKA The board is flipped for the black's perspective, instead of rotated like in the current master PSQT values for each feature the feature transformer now outputs a part that is fowarded directly to the output and allows learning piece values more directly than the previous network architecture. The effect is visible for high imbalance positions, where the current master network outputs evaluations skewed towards zero. 8 PSQT values per feature, chosen based on (popcount(pos.pieces()) - 1) / 4 initialized to classical material values on the start of the training 8 subnetworks (512x2->16->32->1), chosen based on (popcount(pos.pieces()) - 1) / 4 only one subnetwork is evaluated for any position, no or marginal speed loss A diagram of the network is available: A more complete description: closes Bench: 3806488
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