transformers/docs/source/en/model_doc/phobert.md

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# PhoBERT

<div class="flex flex-wrap space-x-1">
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</div>

## Overview

The PhoBERT model was proposed in [PhoBERT: Pre-trained language models for Vietnamese](https://www.aclweb.org/anthology/2020.findings-emnlp.92.pdf) by Dat Quoc Nguyen, Anh Tuan Nguyen.

The abstract from the paper is the following:

*We present PhoBERT with two versions, PhoBERT-base and PhoBERT-large, the first public large-scale monolingual
language models pre-trained for Vietnamese. Experimental results show that PhoBERT consistently outperforms the recent
best pre-trained multilingual model XLM-R (Conneau et al., 2020) and improves the state-of-the-art in multiple
Vietnamese-specific NLP tasks including Part-of-speech tagging, Dependency parsing, Named-entity recognition and
Natural language inference.*

This model was contributed by [dqnguyen](https://huggingface.co/dqnguyen). The original code can be found [here](https://github.com/VinAIResearch/PhoBERT).

## Usage example

```python
>>> import torch
>>> from transformers import AutoModel, AutoTokenizer

>>> phobert = AutoModel.from_pretrained("vinai/phobert-base")
>>> tokenizer = AutoTokenizer.from_pretrained("vinai/phobert-base")

>>> # INPUT TEXT MUST BE ALREADY WORD-SEGMENTED!
>>> line = "Tôi là sinh_viên trường đại_học Công_nghệ ."

>>> input_ids = torch.tensor([tokenizer.encode(line)])

>>> with torch.no_grad():
...     features = phobert(input_ids)  # Models outputs are now tuples

>>> # With TensorFlow 2.0+:
>>> # from transformers import TFAutoModel
>>> # phobert = TFAutoModel.from_pretrained("vinai/phobert-base")
```

<Tip> 

PhoBERT implementation is the same as BERT, except for tokenization. Refer to [BERT documentation](bert) for information on 
configuration classes and their parameters. PhoBERT-specific tokenizer is documented below.  

</Tip>

## PhobertTokenizer

[[autodoc]] PhobertTokenizer