On the Effectiveness of Offline RL for Dialogue Response Generation

This repository contains code for the paper, On the Effectiveness of Offline RL for Dialogue Response Generation, presented at ICML 2023.

Installation

git clone git@github.com:asappresearch/dialogue-offline-rl.git
cd dialogue-offline-rl
pyenv virtualenv dialogue-offline-rl
pyenv activate dialogue-offline-rl

Install the required packages:

pip install -r requirements.txt

Model Checkpoints

Model	Links
Base model (tf)	ABCD, MultiWoz-2.2, TaskMaster-3
Fine Tune on Top Returns (tf_top)	ABCD, MultiWoz-2.2, TaskMaster-3
Decision Transformers: Condition on Return (dt)	ABCD, MultiWoz-2.2, TaskMaster-3
Off-policy Q-learning (ilql)	ABCD, MultiWoz-2.2, TaskMaster-3

Data Processing

1. Create Base Datasets and TF Model

Download and create datasets for training the base TF model:

for dataset in abcd multi_woz taskmaster3; do
    bash scripts/process_data/download_process_${dataset}.sh
done

Train the base TF model by executing:

bash scripts/train/train_base_tf_distilgpt2.sh {dataset} {ngpu}

for example, bash scripts/train/train_base_tf_model_distilgpt2.sh abcd 4

2. Create Offline RL Datasets

To generate datasets for all three methods (tf_top, dt, ilql), we need the path to the base TF model (model_path):

for split in train val test; do
    python scripts/process_data/prepare_offline_rl_data.py --model_path_tf {model_path_tf} --save_path {save_path} --split ${split}
done

Training Offline RL Models

For training, we provide scripts for each of the three methods (tf_top, dt, ilql):

1. Fine Tune on Top Returns, tf_top

bash scripts/train/train_offline_rl_distilgpt2.sh tf_top {dataset} {ngpu}

for example, bash scripts/train/train_offline_rl_distilgpt2.sh tf_top abcd 4

2. Decision Transformers: Condition on Return, dt

bash scripts/train/train_offline_rl_distilgpt2.sh dt {dataset} {ngpu}

for example, bash scripts/train/train_offline_rl_distilgpt2.sh dt abcd 4

3. Off-policy Q-learning, ilql

First, install trlx from a fork at this location. Then execute the command:

python scripts/training/run_trlx_ilql.py --config_path config/trlx_ilql_gpt2med.yml --data_path {ilql_data_path}

Evaluation

To evaluate all the models:

python scripts/evaluation/evaluate_reward_metrics.py --dataset {dataset} --method {method} --model_path {model_path} --metrics '["bert_score", "bleurt_score", "meteor", "bleu"]' --save_path {save_path} --num_samples 1000

where, method={tf, tf_top, dt, ilql}, dataset={abcd, multi_woz, taskmaster3}, and model_path is the path to corresponding model. The script will save all the predictions and metrics to a .csv at save_path.

Citation

If you found our code or paper useful, please consider citing:

@inproceedings{sodhi2023offlinerl,
  title={On the Effectiveness of Offline RL for Dialogue Response Generation},
  author={Sodhi, Paloma and Wu, Felix and Elenberg, Ethan R and Weinberger, Kilian Q and McDonald, Ryan},
  booktitle = {International Conference on Machine Learning (ICML)},
  year={2023}
}

License

This project is licensed under the terms of the MIT license.