OpenThai-NER

Fine-tuned Pavarissy/phayathaibert-thainer for Thai Named Entity Recognition (NER) on the JonusNattapong/OpenThai-NER dataset.

Model Details

• Base model: Pavarissy/phayathaibert-thainer
• Task: Token Classification (NER)
• Language: Thai (th)
• License: cc-by-3.0

Intended Use

This model is intended for:

• Extracting named entities from Thai text (people, organizations, locations, etc. depending on your label schema)
• Downstream tasks like document indexing, entity-based search, analytics, and data labeling acceleration

Limitations / Known Issues (Transparent)

• eval_loss is NaN:
  Common causes:

  • fp16 mixed precision numerical instability
  • incorrect label mask handling (-100) in loss
  • invalid label ids in a batch (out of range)
  • occasional overflow if logits become extreme
    If you want to fix it: try disabling fp16, validate labels, and ensure your data collator pads labels with -100.

• Domain shift: Performance may drop on domains/styles not present in training data (e.g., very informal slang, OCR noise, code-mixed text).

• Entity boundary ambiguity: Thai tokenization and spacing can cause boundary errors (span too long/short), especially with uncommon names.

Evaluation

Final evaluation (epoch 3)

• Precision: 0.8565
• Recall: 0.8778
• F1: 0.8670
• Accuracy: 0.9565
• Runtime: 29.8202s

Training summary

Epoch	Training Loss	Validation Loss	Precision	Recall	F1	Accuracy
1	0.369000	NaN	0.787043	0.824356	0.805268	0.932532
2	0.237600	NaN	0.841745	0.855728	0.848679	0.949934
3	0.195900	NaN	0.856493	0.877835	0.867033	0.956475

Validation loss being NaN across epochs reinforces that this is likely a logging/loss-computation issue rather than random corruption, because the metric trend is consistent and improving.

How to Use

Transformers Pipeline

from transformers import AutoTokenizer, AutoModelForTokenClassification, pipeline

repo_id = "JonusNattapong/OpenThai-NER"

tokenizer = AutoTokenizer.from_pretrained(repo_id)
model = AutoModelForTokenClassification.from_pretrained(repo_id)

ner = pipeline("token-classification", model=model, tokenizer=tokenizer, aggregation_strategy="simple")
text = "กรุงเทพมหานครเป็นเมืองหลวงของประเทศไทย และบริษัท ABC จำกัด ตั้งอยู่ที่บางนา"
print(ner(text))

Manual inference

import torch
from transformers import AutoTokenizer, AutoModelForTokenClassification

repo_id = "JonusNattapong/OpenThai-NER"

tokenizer = AutoTokenizer.from_pretrained(repo_id)
model = AutoModelForTokenClassification.from_pretrained(repo_id)

text = "นายสมชายทำงานที่กระทรวงการคลัง"
inputs = tokenizer(text, return_tensors="pt")

with torch.no_grad():
    outputs = model(**inputs)

pred_ids = outputs.logits.argmax(-1)[0].tolist()
tokens = tokenizer.convert_ids_to_tokens(inputs["input_ids"][0])

print(list(zip(tokens, pred_ids)))

Training Details

• Epochs: 3
• Learning Rate: 2e-5
• Batch Size: 16
• Framework: Hugging Face Transformers Trainer

Reproducibility Notes

If you want fully stable loss:

• Set fp16=False (or bf16=True if available)
• Validate label ids are within [0, num_labels-1] or -100
• Ensure the data collator pads labels with -100
• Try gradient clipping (e.g., max_grad_norm=1.0)

Citation

If you use this corpus in your research, please cite:

@dataset{Thainer Model 2025,
  title={Thai Named Entity Recognition},
  author{Nattapong Tapachoom}
  year={2025},
  howpublished={https://github.com/JonusNattapong/Natural-Language-Processing}
}

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Repo: JonusNattapong/OpenThai-NER Base model: Pavarissy/phayathaibert-thainer