metadata

language: fr
datasets:
  - piaf
  - FQuAD
  - SQuAD-FR

dpr-question_encoder-fr_qa-camembert

Description

French DPR model using CamemBERT as base and then fine-tuned on a combo of three French Q&A

Data

French Q&A

We use a combination of three French Q&A datasets:

Training

We are using 90 562 random questions for train and 22 391 for dev. No question in train exists in dev. For each question, we have a single positive_context (the paragraph where the answer to this question is found) and around 30 hard_negtive_contexts. Hard negative contexts are found by querying an ES instance (via bm25 retrieval) and getting the top-k candidates that do not contain the answer.

The files are over here.

Evaluation

We use FQuADv1.0 and French-SQuAD evaluation sets.

Training Script

We use the official Facebook DPR implentation with a slight modification: by default, the code can work with Roberta models, still we changed a single line to make it easier to work with Camembert. This modification can be found over here.

Hyperparameters

python -m torch.distributed.launch --nproc_per_node=8 train_dense_encoder.py \
--max_grad_norm 2.0 --encoder_model_type hf_bert --pretrained_file data/bert-base-multilingual-uncased \
--seed 12345 --sequence_length 256 --warmup_steps 1237 --batch_size 16 --do_lower_case \
--train_file DPR_FR_train.json \
--dev_file  ./data/100_hard_neg_ctxs/DPR_FR_dev.json \
--output_dir ./output/bert --learning_rate 2e-05 --num_train_epochs 35 \
--dev_batch_size 16 --val_av_rank_start_epoch 25 \
--pretrained_model_cfg ./data/bert-base-multilingual-uncased

Evaluation results

We obtain the following evaluation by using FQuAD and SQuAD-FR evaluation (or validation) sets. To obtain these results, we use haystack's evaluation script (we report Retrieval results only).

DPR

FQuAD v1.0 Evaluation

For 2764 out of 3184 questions (86.81%), the answer was in the top-20 candidate passages selected by the retriever.
Retriever Recall: 0.87
Retriever Mean Avg Precision: 0.57

SQuAD-FR Evaluation

For 8945 out of 10018 questions (89.29%), the answer was in the top-20 candidate passages selected by the retriever.
Retriever Recall: 0.89
Retriever Mean Avg Precision: 0.63

BM25

For reference, BM25 gets the results shown below. As in the original paper, regarding SQuAD-like datasets, the results of DPR are consistently superseeded by BM25.

FQuAD v1.0 Evaluation

For 2966 out of 3184 questions (93.15%), the answer was in the top-20 candidate passages selected by the retriever.
Retriever Recall: 0.93
Retriever Mean Avg Precision: 0.74

SQuAD-FR Evaluation

For 9353 out of 10018 questions (93.36%), the answer was in the top-20 candidate passages selected by the retriever.
Retriever Recall: 0.93
Retriever Mean Avg Precision: 0.77

Usage

The results reported here are obtained with the haystack library. To get to similar embeddings using exclusively HF transformers library, you can do the following:

from transformers import AutoTokenizer, AutoModel
query = "Salut, mon chien est-il mignon ?"
tokenizer = AutoTokenizer.from_pretrained("etalab-ia/dpr-question_encoder-fr_qa-camembert",  do_lower_case=True)
input_ids = tokenizer(query, return_tensors='pt')["input_ids"]
model = AutoModel.from_pretrained("etalab-ia/dpr-question_encoder-fr_qa-camembert", return_dict=True)
embeddings = model.forward(input_ids).pooler_output
print(embeddings)

And with haystack (using transformers-3.3.1), we use it as a retriever (note that we reference it from a local path):

retriever = DensePassageRetriever(
    document_store=document_store,
    query_embedding_model="etalab-ia/dpr-question_encoder-fr_qa-camembert",
    passage_embedding_model="etalab-ia/dpr-ctx_encoder-fr_qa-camembert",
    model_version=dpr_model_tag,
    infer_tokenizer_classes=True,
)

Acknowledgments

This work was performed using HPC resources from GENCI–IDRIS (Grant 2020-AD011011224).

Citations

Datasets

PIAF

@inproceedings{KeraronLBAMSSS20,
  author    = {Rachel Keraron and
               Guillaume Lancrenon and
               Mathilde Bras and
               Fr{\'{e}}d{\'{e}}ric Allary and
               Gilles Moyse and
               Thomas Scialom and
               Edmundo{-}Pavel Soriano{-}Morales and
               Jacopo Staiano},
  title     = {Project {PIAF:} Building a Native French Question-Answering Dataset},
  booktitle = {{LREC}},
  pages     = {5481--5490},
  publisher = {European Language Resources Association},
  year      = {2020}
}

FQuAD

@article{dHoffschmidt2020FQuADFQ,
  title={FQuAD: French Question Answering Dataset},
  author={Martin d'Hoffschmidt and Maxime Vidal and Wacim Belblidia and Tom Brendl'e and Quentin Heinrich},
  journal={ArXiv},
  year={2020},
  volume={abs/2002.06071}
}

SQuAD-FR

 @MISC{kabbadj2018,
   author =       "Kabbadj, Ali",
   title =        "Something new in French Text Mining and Information Extraction (Universal Chatbot): Largest Q&A French training dataset (110 000+) ",
   editor =       "linkedin.com",
   month =        "November",
   year =         "2018",
   url =          "\url{https://www.linkedin.com/pulse/something-new-french-text-mining-information-chatbot-largest-kabbadj/}",
   note =         "[Online; posted 11-November-2018]",
 }

Models

CamemBERT

HF model card : https://huggingface.co./camembert-base

@inproceedings{martin2020camembert,
  title={CamemBERT: a Tasty French Language Model},
  author={Martin, Louis and Muller, Benjamin and Su{\'a}rez, Pedro Javier Ortiz and Dupont, Yoann and Romary, Laurent and de la Clergerie, {\'E}ric Villemonte and Seddah, Djam{\'e} and Sagot, Beno{\^\i}t},
  booktitle={Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics},
  year={2020}
}

DPR

@misc{karpukhin2020dense,
    title={Dense Passage Retrieval for Open-Domain Question Answering},
    author={Vladimir Karpukhin and Barlas Oğuz and Sewon Min and Patrick Lewis and Ledell Wu and Sergey Edunov and Danqi Chen and Wen-tau Yih},
    year={2020},
    eprint={2004.04906},
    archivePrefix={arXiv},
    primaryClass={cs.CL}
}