Enabling Large Language Models to Generate Text with Citations

*: ALCE is pronounced as /elk/ as ALCE is the Latin word for elk (Europe) or moose (North America).

This repository contains the code and data for paper Enabling Large Language Models to Generate Text with Citations. In this paper, we propose ALCE, a benchmark for Automatic LLMs' Citation Evaluation. ALCE contains three datasets: ASQA, QAMPARI, and ELI5. We provide automatic evaluation code of LLM generations around three dimensions: fluency, correctness, and citation quality. This repository also includes code to reproduce the baselines in our paper.

Quick Links

• Requirements
• Data
• Code Structure
• Reproducing Baselines
• Evaluation
• Human Evaluation
• Bug or Questions
• Citation

Requirements

Please install the latest versions of PyTorch (torch), HuggingFace Transformers (transformers), HuggingFace Accelerate (accelerate), and the OpenAI API package (openai). This codebase is tested on torch==2.1.0.dev20230514+cu118, transformers==4.28.1, accelerate==0.17.1, and openai==0.27.4 with Python 3.9.7.

Data

You can download datasets (along with retrieval results) by running the following command:

bash download_data.sh

All the data will be stored in data/. Our data included top-100 DPR/GTR retrieved results for ASQA and QAMPARI, and top-100 BM25 retrieved results for ELI5. We also provide reranked oracle retrieval results, where top-5 passages can achieve the same recall as the original top-100 recall.

Retrieval

You can reproduce the passage retrieval step with the following command:

python retrieval.py --data {path/to/data} --retriever {bm25/gtr} --output_file {path/to/output}

There are additional packages required for the retrieval steps. Specifically, you need to install pyserini==0.21.0(their github repo is helpful) and sentence-transformers==2.2.2.

For the BM25 retrieval over Common Crawl using Sphere, you must first download the index from the Sphere repo, and set the environmental variable BM25_SPHERE_PATH to the path of the downloaded index. Specifically, you can use the following command:

wget -P faiss_index https://dl.fbaipublicfiles.com/sphere/sphere_sparse_index.tar.gz
tar -xzvf faiss_index/sphere_sparse_index.tar.gz -C faiss_index
export BM25_SPHERE_PATH=$PWD/faiss_index

It's important to note that given the large size of the corpus, this step is extremely expensive and time-consuming. We found that larger CPU memory tends to help with the speed.

For GTR, we first build an index using the DPR wikipedia snapshot, which you can obtain using the download script from the DPR repo, and then setting the environmental variable DPR_WIKI_TSV to the path of the tsv file. Specifically, you can use the following command:

wget https://dl.fbaipublicfiles.com/dpr/wikipedia_split/psgs_w100.tsv.gz
gzip -xzvf psgs_w100.tsv.gz
export DPR_WIKI_TSV=$PWD/psgs_w100.tsv

Then, you want to set GTR_EMB to the path of the GTR embeddings of the Wikipedia corpus, and running the retrieval script for the first time will automatically build and save the index. Building the dense index can be expensive for GPU memory (we use 80GB GPUs for this) and time-consuming; the entire index will take about 31GB. If you find this step to be too expensive, you can also download it using:

wget https://huggingface.co/datasets/princeton-nlp/gtr-t5-xxl-wikipedia-psgs_w100-index/resolve/main/gtr_wikipedia_index.pkl
export GTR_EMB=$PWD/gtr_wikipedia_index.pkl

To reproduce the DPR retrieval, we refer the DPR repo, which we used the original DPR checkpoint trained on NQ.

Code Structure

• run.py: run file to reproduce our baseline generations.
• eval.py: eval file to evaluate generations.
• prompts: folder that contains all prompt files.
• configs/: folder that contains all config files to reproduce baselines.
• tools/: misc code (generate summaries/snippets, reranking, etc.)

Reproducing Baselines

You can reproduce baselines from our paper by

python run.py --config configs/{config_name}

You can also overwrite any arguments in the config file or add new arguments simply through command line:

python run.py --config configs/{config_name} --seed 43 --model vicuna-13b

The naming of config files follow the rule of {LLM}_{#demos and #passages}_{retriever}_{method}.yaml. Method names include:

• default corresponds to the Vanilla model in our paper.
• summary corresponds to the Summary model.
• extraction corresponds to the Snippet model.
• interact_doc_id corresponds to the Interact model.
• interact_search corresponds to the InlineSearch model.
• closedbook corresponds to the ClosedBook model.

Our code support both OpenAI API and offline HuggingFace models:

• For OpenAI models (for example, ChatGPT), you need to set the environment variable OPENAI_API_KEY and OPENAI_ORG_ID. If you are using the Azure OpenAI API, you need to set the environment variable of OPENAI_API_KEY and OPENAI_API_BASE. You also need to add the flag --azure.
  • Note that in Azure OpenAI API, ChatGPT's name is different and you should set it by --model gpt-35-turbo.
• For the open-source models, you should set the model name equal to the input of HuggingFace models' .from_pretrained method. This could either be a local directory (e.g. for the older LLaMA models) or a path to the HuggingFace hub.

For detailed argument usage, please refer to run.py.

Model output along with gold answers and run configs will be stored in a json file in result/.

Post-hoc citation

For closed-book models, one can use post_hoc_cite.py to add citations in a post-hoc manner (using GTR-large). To run post-hoc citation, execute

python post_hoc_cite.py --f result/{RESULT JSON FILE NAME} --external_docs data/{CORRESPONDING DATA}

The output file with post-hoc citations will be stored in result/, with a suffix post_hoc_cite.gtr-t5-large-external.

Evaluation

ACLE evaluation is implemented in eval.py.

For ASQA, use the following command

python eval.py --f {path/to/result/file} --citations --qa --mauve

For QAMPARI, use the following command

python eval.py --f {path/to/result/file} --citations

For ELI5, use the following command

python eval.py --f {path/to/result/file} --citations --claims_nli --mauve

The evaluation result will be saved in result/, with the same name as the input and a suffix .score.

Human Evaluation

The results from our human evaluation (Section 6) are located under the directory human_eval. Both the data and the analysis are available, please refer to the directory for details.

Bug or Questions?

If you have any questions related to the code or the paper, feel free to email Tianyu (tianyug@cs.princeton.edu). If you encounter any problems when using the code, or want to report a bug, you can open an issue. Please try to specify the problem with details so we can help you better and quicker!

Citation

Please cite our paper if you use ALCE in your work:

@inproceedings{gao2023enabling,
   title={Enabling Large Language Models to Generate Text with Citations},
   author={Gao, Tianyu and Yen, Howard and Yu, Jiatong and Chen, Danqi},
   year={2023},
   booktitle={Empirical Methods in Natural Language Processing (EMNLP)},
}