chorcat/rukh-pairs-dpo

Preference pairs from the multi-PV Stockfish lines of rukh-positions-eval: the best first move against a legal move at least 100 centipawns worse for the side to move (mates count as 10000). One pair per position, balanced by phase.

Part of Rukh, a chess language model built from scratch as a course on generative and agentic AI. Every derived dataset ships with the exact filters and counts of its manifest.json, so it can be regenerated with rukh data pairs.

Files

File	Bytes	SHA-256
pairs.parquet	418945	cc3e38f73a15afbcd685d2cdbdcaadf329bc621d909cc5e76bdfec661e6812a7

Rows: 13887.

Columns

Column	Description
fen	four-field FEN of the position
chosen	best move (UCI)
rejected	clearly worse legal move (UCI)
cp_chosen	score of chosen from White's point of view (mate = +/-10000)
cp_rejected	score of rejected from White's point of view
phase	opening, middlegame or endgame

Provenance and filters

Source: rukh-positions-eval (from Lichess/chess-position-evaluations).

{
  "min_delta_cp": 100,
  "max_per_phase": 200000,
  "seed": 42,
  "mate_score": 10000,
  "cp_point_of_view": "white",
  "best_line": "deepest; mate for the mover first; then best cp for the side to move",
  "legality": "python-chess",
  "candidates_by_phase": {
    "opening": 14402,
    "middlegame": 50215,
    "endgame": 4629
  },
  "empty_phases": []
}

Counts:

{
  "opening": 4629,
  "middlegame": 4629,
  "endgame": 4629,
  "candidates": 69246
}

Generated on 2026-09-19 with rukh 0.0.1.

License

CC0 1.0. The games, puzzles and evaluations come from the Lichess open database (https://database.lichess.org, https://huggingface.co/Lichess), published under CC0; the derived files keep that license. Please credit Lichess when you use them.