# DeeBERT: Early Exiting for *BERT

This is the code base for the paper [DeeBERT: Dynamic Early Exiting for Accelerating BERT Inference](https://www.aclweb.org/anthology/2020.acl-main.204/), modified from its [original code base](https://github.com/castorini/deebert).

The original code base also has information for downloading sample models that we have trained in advance.

## Usage

There are three scripts in the folder which can be run directly.

In each script, there are several things to modify before running:

* `PATH_TO_DATA`: path to the GLUE dataset.
* `--output_dir`: path for saving fine-tuned models. Default: `./saved_models`.
* `--plot_data_dir`: path for saving evaluation results. Default: `./results`. Results are printed to stdout and also saved to `npy` files in this directory to facilitate plotting figures and further analyses.
* `MODEL_TYPE`: bert or roberta
* `MODEL_SIZE`: base or large
* `DATASET`: SST-2, MRPC, RTE, QNLI, QQP, or MNLI

#### train_deebert.sh

This is for fine-tuning DeeBERT models.

#### eval_deebert.sh

This is for evaluating each exit layer for fine-tuned DeeBERT models.

#### entropy_eval.sh

This is for evaluating fine-tuned DeeBERT models, given a number of different early exit entropy thresholds.



## Citation

Please cite our paper if you find the resource useful:
```
@inproceedings{xin-etal-2020-deebert,
    title = "{D}ee{BERT}: Dynamic Early Exiting for Accelerating {BERT} Inference",
    author = "Xin, Ji  and
      Tang, Raphael  and
      Lee, Jaejun  and
      Yu, Yaoliang  and
      Lin, Jimmy",
    booktitle = "Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics",
    month = jul,
    year = "2020",
    address = "Online",
    publisher = "Association for Computational Linguistics",
    url = "https://www.aclweb.org/anthology/2020.acl-main.204",
    pages = "2246--2251",
}
```