Model reference · open weights

ct2fast-e5-small

Available as managed deployment Embeddings michaelfeil · community Embeddings 1 variants 526 dl/mo

ct2fast-e5-small is an open-weight embedding model from michaelfeil. 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 bymichaelfeil
TypeEmbedding models
TaskEmbeddings
Context512 tokens
Runs withsentence-transformers
Released2023-06-15
Popularity526 downloads / month
LicenceOpen weights

About

What ct2fast-e5-small is

Speedup inference while reducing memory by 2x-4x using int8 inference in C++ on CPU or GPU.

quantized version of intfloat/e5-small-v2

Read the full model card
pip install hf-hub-ctranslate2>=2.12.0 ctranslate2>=3.17.1
# from transformers import AutoTokenizer
model_name = "michaelfeil/ct2fast-e5-small-v2"
model_name_orig="intfloat/e5-small-v2"

from hf_hub_ctranslate2 import EncoderCT2fromHfHub
model = EncoderCT2fromHfHub(
        # load in int8 on CUDA
        model_name_or_path=model_name,
        device="cuda",
        compute_type="int8_float16"
)
outputs = model.generate(
    text=["I like soccer", "I like tennis", "The eiffel tower is in Paris"],
    max_length=64,
) # perform downstream tasks on outputs
outputs["pooler_output"]
outputs["last_hidden_state"]
outputs["attention_mask"]

# alternative, use SentenceTransformer Mix-In
# for end-to-end Sentence embeddings generation
# (not pulling from this CT2fast-HF repo)

from hf_hub_ctranslate2 import CT2SentenceTransformer
model = CT2SentenceTransformer(
    model_name_orig, compute_type="int8_float16", device="cuda"
)
embeddings = model.encode(
    ["I like soccer", "I like tennis", "The eiffel tower is in Paris"],
    batch_size=32,
    convert_to_numpy=True,
    normalize_embeddings=True,
)
print(embeddings.shape, embeddings)
scores = (embeddings @ embeddings.T) * 100

# Hint: you can also host this code via REST API and
# via github.com/michaelfeil/infinity

Checkpoint compatible to ctranslate2>=3.17.1 and hf-hub-ctranslate2>=2.12.0

  • compute_type=int8_float16 for device="cuda"
  • compute_type=int8 for device="cpu"

Converted on 2023-10-13 using

LLama-2 -> removed  token.

Licence and other remarks:

This is just a quantized version. Licence conditions are intended to be idential to original huggingface repo.

Original description

E5-small-v2

Text Embeddings by Weakly-Supervised Contrastive Pre-training. Liang Wang, Nan Yang, Xiaolong Huang, Binxing Jiao, Linjun Yang, Daxin Jiang, Rangan Majumder, Furu Wei, arXiv 2022

This model has 12 layers and the embedding size is 384.

Usage

Below is an example to encode queries and passages from the MS-MARCO passage ranking dataset.

import torch.nn.functional as F

from torch import Tensor
from transformers import AutoTokenizer, AutoModel

def average_pool(last_hidden_states: Tensor,
                 attention_mask: Tensor) -> Tensor:
    last_hidden = last_hidden_states.masked_fill(~attention_mask[..., None].bool(), 0.0)
    return last_hidden.sum(dim=1) / attention_mask.sum(dim=1)[..., None]

# Each input text should start with "query: " or "passage: ".
# For tasks other than retrieval, you can simply use the "query: " prefix.
input_texts = ['query: how much protein should a female eat',
               'query: summit define',
               "passage: As a general guideline, the CDC's average requirement of protein for women ages 19 to 70 is 46 grams per day. But, as you can see from this chart, you'll need to increase that if you're expecting or training for a marathon. Check out the chart below to see how much protein you should be eating each day.",
               "passage: Definition of summit for English Language Learners. : 1  the highest point of a mountain : the top of a mountain. : 2  the highest level. : 3  a meeting or series of meetings between the leaders of two or more governments."]

tokenizer = AutoTokenizer.from_pretrained('intfloat/e5-small-v2')
model = AutoModel.from_pretrained('intfloat/e5-small-v2')

# Tokenize the input texts
batch_dict = tokenizer(input_texts, max_length=512, padding=True, truncation=True, return_tensors='pt')

outputs = model(**batch_dict)
embeddings = average_pool(outputs.last_hidden_state, batch_dict['attention_mask'])

# normalize embeddings
embeddings = F.normalize(embeddings, p=2, dim=1)
scores = (embeddings[:2] @ embeddings[2:].T) * 100
print(scores.tolist())

Training Details

Please refer to our paper at https://arxiv.org/pdf/2212.03533.pdf.

Benchmark Evaluation

Check out unilm/e5 to reproduce evaluation results on the BEIR and MTEB benchmark.

Support for Sentence Transformers

Below is an example for usage with sentence_transformers.

from sentence_transformers import SentenceTransformer
model = SentenceTransformer('intfloat/e5-small-v2')
input_texts = [
    'query: how much protein should a female eat',
    'query: summit define',
    "passage: As a general guideline, the CDC's average requirement of protein for women ages 19 to 70 is 46 grams per day. But, as you can see from this chart, you'll need to increase that if you're expecting or training for a marathon. Check out the chart below to see how much protein you should be eating each day.",
    "passage: Definition of summit for English Language Learners. : 1  the highest point of a mountain : the top of a mountain. : 2  the highest level. : 3  a meeting or series of meetings between the leaders of two or more governments."
]
embeddings = model.encode(input_texts, normalize_embeddings=True)

Package requirements

pip install sentence_transformers~=2.2.2

Contributors: michaelfeil

FAQ

1. Do I need to add the prefix "query: " and "passage: " to input texts?

Yes, this is how the model is trained, otherwise you will see a performance degradation.

Here are some rules of thumb:

  • Use "query: " and "passage: " correspondingly for asymmetric tasks such as passage retrieval in open QA, ad-hoc information retrieval.

  • Use "query: " prefix for symmetric tasks such as semantic similarity, paraphrase retrieval.

  • Use "query: " prefix i

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

Benchmarks

Reported results

As published on the model card — the maker's own numbers, not measured by AxForge.

TaskDatasetMetricScore
ClassificationMTEB AmazonCounterfactualClassification (en)accuracy77.597
ClassificationMTEB AmazonCounterfactualClassification (en)ap41.671
ClassificationMTEB AmazonCounterfactualClassification (en)f171.865
ClassificationMTEB AmazonPolarityClassificationaccuracy91.266
ClassificationMTEB AmazonPolarityClassificationap87.676
ClassificationMTEB AmazonPolarityClassificationf191.243
ClassificationMTEB AmazonReviewsClassification (en)accuracy45.882
ClassificationMTEB AmazonReviewsClassification (en)f145.081
RetrievalMTEB ArguAnamap_at_120.697
RetrievalMTEB ArguAnamap_at_1033.975
RetrievalMTEB ArguAnamap_at_10035.223
RetrievalMTEB ArguAnamap_at_100035.260
RetrievalMTEB ArguAnamap_at_329.777
RetrievalMTEB ArguAnamap_at_532.035
RetrievalMTEB ArguAnamrr_at_120.982
RetrievalMTEB ArguAnamrr_at_1034.094
RetrievalMTEB ArguAnamrr_at_10035.343
RetrievalMTEB ArguAnamrr_at_100035.380
RetrievalMTEB ArguAnamrr_at_329.884
RetrievalMTEB ArguAnamrr_at_532.142
RetrievalMTEB ArguAnandcg_at_120.697
RetrievalMTEB ArguAnandcg_at_1041.668
RetrievalMTEB ArguAnandcg_at_10047.397
RetrievalMTEB ArguAnandcg_at_100048.305

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys ct2fast-e5-small for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (ct2fast-e5-small 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":"ct2fast-e5-small","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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