| --- |
| library_name: tokenizers |
| tags: |
| - tokenizer |
| - multilingual |
| - byte-level-bpe |
| - indigenous-languages |
| - tachiwin |
| --- |
| |
| # Tachiwin multilingual tokenizer |
|
|
| A multilingual ByteLevel-BPE tokenizer trained with Hugging Face Tokenizers. |
|
|
| ## Corpus weighting |
|
|
| | Component | Target | |
| |---|---:| |
| | Modern + old exotic-language data | 70% | |
| | English | 10% | |
| | Spanish | 10% | |
| | Code | 10% | |
|
|
| The complete available exotic-language corpus is used as the 70% anchor. |
| Its existing modern/old composition is preserved. |
|
|
| ## Tokenizer |
|
|
| - Model: BPE, trained via `Tokenizer.train_from_iterator` over a streaming |
| line generator (constant memory regardless of corpus size) |
| - Vocabulary target: 256,000 |
| - Initial alphabet: complete ByteLevel alphabet |
| - ByteLevel GPT-2 regex: disabled |
| - Unicode normalizer: none |
| - Special tokens: 274 |
| - Human-language tags: 240 |
|
|
| ## Corpus size |
|
|
| Total materialized corpus: 360,820,186 bytes (0.336 GiB) |
|
|
| ## Evaluation |
|
|
| The tokenizer was evaluated against the Tachiwin language catalogue. |
| Languages without text samples are skipped. For each language, all |
| available samples are concatenated ONLY within that language for aggregate |
| fertility statistics. Metrics: characters/token, tokens/character, UTF-8 |
| bytes/token, tokens/UTF-8 byte, exact round-trip preservation. |
|
|
| ## Important training note |
|
|
| The Hugging Face BPE trainer does not expose an internal resumable |
| merge-state checkpoint. The recipe therefore treats the completed |
| `tokenizer.json` as the training checkpoint: |
|
|
| - corpus preparation is resumable (both the exotic streaming pass and the |
| capped external-corpus downloads reuse existing shards); |
| - recipe/statistics/checksums are stored in `recipe/`; |
| - if `tokenizer.json` already exists, subsequent runs skip BPE training; |
| - an interrupted BPE computation itself must be restarted. |
|
|
| ## Repository evaluation artifacts |
|
|
| - evaluation/catalogue.json |
| - evaluation/language_fertility.csv |
| - evaluation/language_fertility.json |
| - evaluation/evaluation_summary.json |
| |
