Chonky is a transformer model that intelligently segments text into meaningful semantic chunks. This model can be used in the RAG systems.
🆕 Now multilingual!
Model Description
The model processes text and divides it into semantically coherent segments. These chunks can then be fed into embedding-based retrieval systems or language models as part of a RAG pipeline.
⚠️This model was fine-tuned on sequence of length 1024 (by default mmBERT supports sequence length up to 8192).
How to use
I've made a small python library for this model: chonky
Here is the usage:
from src.chonky import ParagraphSplitter # on the first run it will download the transformer model splitter = ParagraphSplitter( model_id="mirth/chonky_mmbert_small_multilingual_1", device="cpu" ) text = ( "Before college the two main things I worked on, outside of school, were writing and programming. " "I didn't write essays. I wrote what beginning writers were supposed to write then, and probably still are: short stories. " "My stories were awful. They had hardly any plot, just characters with strong feelings, which I imagined made them deep. " "The first programs I tried writing were on the IBM 1401 that our school district used for what was then called 'data processing.' " "This was in 9th grade, so I was 13 or 14. The school district's 1401 happened to be in the basement of our junior high school, " "and my friend Rich Draves and I got permission to use it. It was like a mini Bond villain's lair down there, with all these alien-looking machines — " "CPU, disk drives, printer, card reader — sitting up on a raised floor under bright fluorescent lights." ) for chunk in splitter(text): print(chunk) print("--")Sample Output:
Before college the two main things I worked on, outside of school, were writing and programming. I didn't write essays. I wrote what beginning writers were supposed to write then, and probably still are: short stories. My stories were awful. They had hardly any plot, just characters with strong feelings, which I imagined made them deep -- . The first programs I tried writing were on the IBM 1401 that our school district used for what was then called 'data processing.' This was in 9th grade, so I was 13 or 14. The school district's 1401 happened to be in the basement of our junior high school, and my friend Rich Draves and I got permission to use it. It was like a mini Bond villain's lair down there, with all these alien-looking machines — CPU, disk drives, printer, card reader — sitting up on a raised floor under bright fluorescent lights. --But you can use this model using standart NER pipeline:
from transformers import AutoTokenizer, AutoModelForTokenClassification, pipeline model_name = "mirth/chonky_mmbert_small_multilingual_1" tokenizer = AutoTokenizer.from_pretrained(model_name, model_max_length=1024) id2label = { 0: "O", 1: "separator", } label2id = { "O": 0, "separator": 1, } model = AutoModelForTokenClassification.from_pretrained( model_name, num_labels=2, id2label=id2label, label2id=label2id, ) pipe = pipeline("ner", model=model, tokenizer=tokenizer, aggregation_strategy="simple") text = ( "Before college the two main things I worked on, outside of school, were writing and programming. " "I didn't write essays. I wrote what beginning writers were supposed to write then, and probably still are: short stories. " "My stories were awful. They had hardly any plot, just characters with strong feelings, which I imagined made them deep. " "The first programs I tried writing were on the IBM 1401 that our school district used for what was then called 'data processing.' " "This was in 9th grade, so I was 13 or 14. The school district's 1401 happened to be in the basement of our junior high school, " "and my friend Rich Draves and I got permission to use it. It was like a mini Bond villain's lair down there, with all these alien-looking machines — " "CPU, disk drives, printer, card reader — sitting up on a raised floor under bright fluorescent lights." ) pipe(text)Sample output
[{'entity_group': 'separator', 'score': np.float32(0.66304857), 'word': ' deep', 'start': 332, 'end': 337}]Training Data
The model was trained to split paragraphs from minipile, bookcorpus and Project Gutenberg datasets.
Metrics
Token based F1-score.
Project Gutenberg validation:
| chonky_mmbert_small_multi_1 🆕 | 0.88 | 0.78 | 0.91 | 0.93 | 0.86 | 0.81 | 0.81 | 0.88 | 0.97 | 0.91 | 0.11 |
| chonky_modernbert_large_1 | 0.53 | 0.43 | 0.48 | 0.51 | 0.56 | 0.21 | 0.65 | 0.53 | 0.87 | 0.51 | 0.33 |
| chonky_modernbert_base_1 | 0.42 | 0.38 | 0.34 | 0.4 | 0.33 | 0.22 | 0.41 | 0.35 | 0.27 | 0.31 | 0.26 |
| chonky_distilbert_base_uncased_1 | 0.19 | 0.3 | 0.17 | 0.2 | 0.18 | 0.04 | 0.27 | 0.21 | 0.22 | 0.19 | 0.15 |
| Number of val tokens | 1m | 1m | 1m | 1m | 1m | 1m | 38k | 1m | 24k | 1m | 132k |
Various english datasets:
| chonkY_modernbert_large_1 | 0.79 | 0.29 | 0.69 | 0.17 |
| chonkY_modernbert_base_1 | 0.72 | 0.08 | 0.63 | 0.15 |
| chonkY_distilbert_base_uncased_1 | 0.69 | 0.05 | 0.52 | 0.15 |
| chonky_mmbert_small_multilingual_1 🆕 | 0.72 | 0.2 | 0.56 | 0.13 |
Hardware
Model was fine-tuned on a single H100 for a several hours
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