AdaMLLab/ThaiMix

ThaiMix (https://arxiv.org/abs/2512.18834) is a Thai pretraining corpus containing 70 billion tokens across 81 million documents (in the minhash subset). Rather than scraping the web again, ThaiMix combines five publicly available Thai datasets, applies Thai-specific quality filtering, and performs cross-dataset deduplication.

Subsets

Subset	Documents	Tokens	Description
minhash_deduped	81.3M	70.5B	Document-level MinHash deduplication
matched	10.9M	12.3B	Documents appearing in 2+ source datasets

The matched subset uses cross-dataset agreement as a signal for quality.

Usage

from datasets import load_dataset

ds = load_dataset("AdaMLLab/ThaiMix", "minhash_deduped")
ds = load_dataset("AdaMLLab/ThaiMix", "matched")

Sources

Tokens were counted using meta-llama/Llama-3.2-3B's tokenizer.

Source	Survival Rate
HPLT 2.0	75.1%
C4	72.6%
SEA-CC	70.7%
CulturaX	69.0%
FineWeb-2	61.7%

Pipeline

1. Quality filtering with Thai-specific thresholds (Thai script ratio, repetition patterns, language identification)
2. Document-level MinHash deduplication (5-gram shingles, 14 bands, 8 hashes per band, similarity threshold 0.8)
3. Cross-source matching to identify documents appearing in 2+ independent sources

Citation

@misc{alrashed2025mixminmatch,
      title={Mix, MinHash, and Match: Cross-Source Agreement for Multilingual Pretraining Datasets}, 
      author={Sultan Alrashed and Francesco Orabona},
      year={2025},
      eprint={2512.18834v2},
      archivePrefix={arXiv},
      primaryClass={cs.CL},
      url={https://arxiv.org/abs/2512.18834v2}, 
}

License

See individual source dataset licenses.