avewright/exp186-sf-multipv-2m

exp186 Stockfish MultiPV soft targets (~2M)

Local Stockfish 18 full-strength MultiPV harvest for chess transformer soft-policy training.

Contents

• —data/positions_*.jsonl — ~2,000,000 positions (400 shards)
• —soft_cache.pt — training-ready tensor cache (compact move vocab 1968)

Labeling

• —Engine: Stockfish 18 (full strength, no UCI_LimitStrength)
• —MultiPV: 8
• —Depths: sampled in [2, 8] (weighted toward mid depths)
• —Soft probs: softmax(cp / τ) with τ=120

Schema

Each JSONL line has fen, best_move, best_cp, soft_targets (up to 8 moves with uci/prob/cp), label_depth, phase, source.

Stats

• —written: 1998784
• —depth_hist: {"2": 209465, "3": 315864, "4": 421147, "5": 314654, "6": 210726, "7": 104881, "8": 105176}
• —uploaded_at: 2026-07-10T01:59:56.219054+00:00