Model reference · open weights

distilbert-dot-tas_b-b256-msmarco

Available as managed deployment Embeddings sebastian-hofstaetter · community Embeddings 1 variants 1k dl/mo

distilbert-dot-tas_b-b256-msmarco is an open-weight embedding model from sebastian-hofstaetter. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.

Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.

What it is

Released bysebastian-hofstaetter
TypeEmbedding models
TaskEmbeddings
Context512 tokens
Runs withtransformers
Released2022-03-02
Popularity1k downloads / month
LicenceUnknown

About

What distilbert-dot-tas_b-b256-msmarco is

We provide a retrieval trained DistilBert-based model (we call the dual-encoder then dot-product scoring architecture BERT_Dot) trained with Balanced Topic Aware Sampling on MSMARCO-Passage.

This instance was trained with a batch size of 256 and can be used to re-rank a candidate set or directly for a vector index based dense retrieval. The architecture is a 6-layer DistilBERT, without architecture additions or modifications (we only change the weights during training) - to receive a query/passage representation we pool the CLS vector. We use the same BERT layers for both query and passage encoding (yields better results, and lowers memory requirements).

If you want to know more about our efficient (can be done on a single consumer GPU in 48 hours) batch composition procedure and dual supervision for dense retrieval training, check out our paper: https://arxiv.org/abs/2104.06967 🎉

For more information and a minimal usage example please visit: https://github.com/sebastian-hofstaetter/tas-balanced-dense-retrieval

Read the full model card

Effectiveness on MSMARCO Passage & TREC-DL'19

We trained our model on the MSMARCO standard ("small"-400K query) training triples re-sampled with our TAS-B method. As teacher models we used the BERT_CAT pairwise scores as well as the ColBERT model for in-batch-negative signals published here: https://github.com/sebastian-hofstaetter/neural-ranking-kd

MSMARCO-DEV (7K)

MRR@10NDCG@10Recall@1K
BM25.194.241.857
TAS-B BERT_Dot (Retrieval).347.410.978

TREC-DL'19

For MRR and Recall we use the recommended binarization point of the graded relevance of 2. This might skew the results when compared to other binarization point numbers.

MRR@10NDCG@10Recall@1K
BM25.689.501.739
TAS-B BERT_Dot (Retrieval).883.717.843

TREC-DL'20

For MRR and Recall we use the recommended binarization point of the graded relevance of 2. This might skew the results when compared to other binarization point numbers.

MRR@10NDCG@10Recall@1K
BM25.649.475.806
TAS-B BERT_Dot (Retrieval).843.686.875

For more baselines, info and analysis, please see the paper: https://arxiv.org/abs/2104.06967

Limitations & Bias

  • The model inherits social biases from both DistilBERT and MSMARCO.

  • The model is only trained on relatively short passages of MSMARCO (avg. 60 words length), so it might struggle with longer text.

Citation

If you use our model checkpoint please cite our work as:

@inproceedings{Hofstaetter2021_tasb_dense_retrieval,
 author = {Sebastian Hofst{\"a}tter and Sheng-Chieh Lin and Jheng-Hong Yang and Jimmy Lin and Allan Hanbury},
 title = {{Efficiently Teaching an Effective Dense Retriever with Balanced Topic Aware Sampling}},
 booktitle = {Proc. of SIGIR},
 year = {2021},
}

From the published model card. Full card on the HuggingFace links in the sidebar.

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys distilbert-dot-tas-b-b256-msmarco for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (distilbert-dot-tas-b-b256-msmarco below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/embeddings \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"distilbert-dot-tas-b-b256-msmarco","input":"text to embed"}'

Create an account — your API key is available in the console. 3M free tokens every 30 days with every new account.

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