| --- |
| dataset_info: |
| features: |
| - name: text |
| dtype: string |
| - name: players |
| dtype: string |
| - name: num_moves |
| dtype: int16 |
| - name: n_passes |
| dtype: int16 |
| splits: |
| - name: train |
| num_bytes: 6197484135 |
| num_examples: 20000000 |
| - name: test |
| num_bytes: 1176312920 |
| num_examples: 3796010 |
| download_size: 2805767980 |
| dataset_size: 7373797055 |
| configs: |
| - config_name: default |
| data_files: |
| - split: train |
| path: data/train-* |
| - split: test |
| path: data/test-* |
| --- |
| # Othello (synthetic) |
|
|
| Uniformly-random **legal Othello** games -- a regeneration of the synthetic training data from [*Emergent World Representations: Exploring a Sequence Model Trained on a Synthetic Task*](https://arxiv.org/abs/2210.13382) (Li et al., ICLR 2023), at the paper's own scale, since the original Google Drive release is no longer reachable. |
|
|
| Games are generated by the **original** Othello engine from [likenneth/othello_world](https://github.com/likenneth/othello_world) (vendored in this repo under `third_party/othello_world/`), driven by `data/othello_game.py`, which seeds each game by index so the dataset is reproducible and the multiprocessing workers stay independent. |
|
|
| ## The game |
|
|
| - Standard 8x8 Othello: four discs pre-placed in the centre, **Black moves first**, a move must bracket at least one contiguous line of opponent discs (in any of the 8 directions) between the new disc and one of your own, and every bracketed line flips. |
| - **Every move here is legal but otherwise random** -- uniform over the legal moves at each position. No strategy, no engine, no human games. |
| - **Passing.** A player with no legal move passes and the opponent moves again, so the colours in a game do **not** strictly alternate. Never infer the mover from the move index -- use the `players` column. |
| - A game ends when neither player can move, which is a full board (60 moves) or, occasionally, 59. |
|
|
| ## Notation |
|
|
| Cells use the upstream repo's own string form (`permit_reverse`): a lowercase **row letter `a`-`h`** followed by a **column digit `1`-`8`**, e.g. `d5`, with flat board index `row * 8 + col`. Note the row comes first, which is transposed relative to standard Othello notation; it is kept so cell names, board indices and Li et al.'s own evaluation code line up without a translation layer. |
|
|
| ## Columns |
|
|
| - **`text`** — the moves in play order, comma separated, e.g. `f5, f4, c3, ...`. The number of moves is the game's *decision-point* count. |
| - **`players`** — the colour that played each move, as a string of `B`/`W` of the same length, e.g. `BWBWWB...`. A repeated letter marks a pass by the other colour. |
| - **`num_moves`** — decision points in the game (59 or 60). |
| - **`n_passes`** — how many moves were reached because the other colour had to pass. |
|
|
| ## Splits |
|
|
| | Split | Games | Decision points | Avg moves/game | Games with a pass | Passes | |
| |---|---:|---:|---:|---:|---:| |
| | `train` | 20,000,000 | 1,199,496,827 | 59.97 | 6,889,947 (34.4%) | 8,924,951 (0.74%) | |
| | `test` | 3,796,010 | 227,670,564 | 59.98 | 1,308,791 (34.5%) | 1,696,278 (0.75%) | |
|
|
| Split sizes are the paper's own (20,000,000 train, 3,796,010 validation). The two splits are disjoint by construction: train draws seeds from 0 upward, `test` from 1,000,000,000 upward, and games are deduplicated by move sequence across both. |
|
|
| ## Usage |
|
|
| ```python |
| from datasets import load_dataset |
| ds = load_dataset("cfierro/othello-synthetic") |
| game = ds["train"][0] |
| moves = [m.strip() for m in game["text"].split(",")] |
| colors = list(game["players"]) # "B"/"W" per move |
| ``` |
|
|
| Board state, legal moves and per-position replay: `data/othello_game.py` (`decision_points`, `render`). |
|
|
| ## Provenance |
|
|
| - **Code**: generated with [`data/push_othello_dataset.py` @ `8bc64a1c1e`](https://github.com/constanzafierro/rules-learning/blob/8bc64a1c1eca92528038b359fa15dfa6db753c30/data/push_othello_dataset.py). |
| > ⚠️ The working tree had **uncommitted changes** when this dataset was generated, so the linked commit may not exactly match the code that ran. Commit the generator before generating for a faithful link. |
|
|
| - **Built**: 2026-08-05T18:40:22 |
| - **Command**: |
|
|
| ```bash |
| python data/push_othello_dataset.py --out_dir /projects/nlp/data/constanzam/knowledge-ft/othello_gen_games --num_proc 64 |
| ``` |
|
|
| - **Resolved arguments**: |
|
|
| ```json |
| { |
| "repo": "cfierro/othello-synthetic", |
| "out_dir": "/projects/nlp/data/constanzam/knowledge-ft/othello_gen_games", |
| "train_games": 20000000, |
| "test_games": 3796010, |
| "test_seed_offset": 1000000000, |
| "num_proc": 64, |
| "no_dedup": false, |
| "skip_push": false, |
| "push_only": false, |
| "dry_run": false, |
| "private": false |
| } |
| ``` |
|
|
