Model reference · open weights

specter2

Embeddings allenai Embeddings 1 build Open weights 778k dl/mo

specter2 is an open-weight embedding model from allenai. specter2_base (BF16) weighs 440 MB; the smallest configuration that runs it is RTX 3060 12 GB.

  • SPECTER2 is a feature-extraction model developed by Allen AI for generating task-specific embeddings of scientific papers.
  • It is built on a BERT-base-uncased architecture and operates with a 512-token context length in English.
  • The model is released under the Apache 2.0 license and is designed to be used with adapters for tasks such as classification, regression, and retrieval.

Summary of the allenai/specter2_base model card, 2026-10-01

What it is

Released byallenai
Released2023-02-16
VRAM440 MB for the weights

What it runs on

Memory and cards for specter2_base (BF16)

440 MBweights, file size
1.1 GBruntime overhead
CardRunsMemory
RTX 3060 12 GBfits11.6 GB
RTX 4060 Ti 16 GBfits15.4 GB
RTX 3090 24 GBfits23.4 GB
RTX 4090 24 GBfits23.4 GB
RTX 5090 32 GBfits31.0 GB
L40S 48 GBfits44.0 GB
A100 80 GBfits78.2 GB
H100 80 GBfits78.1 GB
RTX PRO 6000 Blackwell 96 GBfits93.8 GB
DGX Spark (GB10) 128 GB unifiedfits107 GB
H200 141 GBfits138 GB
B200 180 GBfits176 GB

From the model card

What allenai says about specter2

Read the model card

SPECTER2

SPECTER2 is the successor to SPECTER and is capable of generating task specific embeddings for scientific tasks when paired with adapters. This is the base model to be used along with the adapters. Given the combination of title and abstract of a scientific paper or a short texual query, the model can be used to generate effective embeddings to be used in downstream applications.

Note:For general embedding purposes, please use allenai/specter2.

To get the best performance on a downstream task type please load the associated adapter with the base model as in the example below.

Dec 2023 Update:

Model usage updated to be compatible with latest versions of transformers and adapters (newly released update to adapter-transformers) libraries.

Aug 2023 Update:

  1. The SPECTER2 Base and proximity adapter models have been renamed in Hugging Face based upon usage patterns as follows:
Old NameNew Name
allenai/specter2allenai/specter2_base
allenai/specter2_proximityallenai/specter2
  1. We have a parallel version (termed aug2023refresh) where the base transformer encoder version is pre-trained on a collection of newer papers (published after 2018). However, for benchmarking purposes, please continue using the current version.

An adapter for the allenai/specter2_base model that was trained on the allenai/scirepeval dataset.

This adapter was created for usage with the adapters library.

Model Details

Model Description

SPECTER2 has been trained on over 6M triplets of scientific paper citations, which are available here. Post that it is trained with additionally attached task format specific adapter modules on all the SciRepEval training tasks.

Task Formats trained on:

  • Classification
  • Regression
  • Proximity (Retrieval)
  • Adhoc Search

It builds on the work done in SciRepEval: A Multi-Format Benchmark for Scientific Document Representations and we evaluate the trained model on this benchmark as well.

  • Developed by: Amanpreet Singh, Mike D'Arcy, Arman Cohan, Doug Downey, Sergey Feldman
  • Shared by : Allen AI
  • Model type: bert-base-uncased + adapters
  • License: Apache 2.0
  • Finetuned from model: allenai/scibert.

Model Sources

Uses

Direct Use

ModelName and HF linkDescription
Proximity*allenai/specter2Encode papers as queries and candidates eg. Link Prediction, Nearest Neighbor Search
Adhoc Queryallenai/specter2_adhoc_queryEncode short raw text queries for search tasks. (Candidate papers can be encoded with the proximity adapter)
Classificationallenai/specter2_classificationEncode papers to feed into linear classifiers as features
Regressionallenai/specter2_regressionEncode papers to feed into linear regressors as features

*Proximity model should suffice for downstream task types not mentioned above

from transformers import AutoTokenizer
from adapters import AutoAdapterModel

# load model and tokenizer
tokenizer = AutoTokenizer.from_pretrained('allenai/specter2_base')

#load base model
model = AutoAdapterModel.from_pretrained('allenai/specter2_base')

#load the adapter(s) as per the required task, provide an identifier for the adapter in load_as argument and activate it
model.load_adapter("allenai/specter2", source="hf", load_as="proximity", set_active=True)
#other possibilities: allenai/specter2_

papers = [{'title': 'BERT', 'abstract': 'We introduce a new language representation model called BERT'},
          {'title': 'Attention is all you need', 'abstract': ' The dominant sequence transduction models are based on complex recurrent or convolutional neural networks'}]

# concatenate title and abstract
text_batch = [d['title'] + tokenizer.sep_token + (d.get('abstract') or '') for d in papers]
# preprocess the input
inputs = self.tokenizer(text_batch, padding=True, truncation=True,
                                   return_tensors="pt", return_token_type_ids=False, max_length=512)
output = model(**inputs)
# take the first token in the batch as the embedding
embeddings = output.last_hidden_state[:, 0, :]

Downstream Use

For evaluation and downstream usage, please refer to https://github.com/allenai/scirepeval/blob/main/evaluation/INFERENCE.md.

Training Details

Training Data

The base model is trained on citation links between papers and the adapters are trained on 8 large scale tasks across the four formats. All the data is a part of SciRepEval benchmark and is available here.

The citation link are triplets in the form

{"query": {"title": ..., "abstract": ...}, "pos": {"title": ..., "abstract": ...}, "neg":

Quoted from the model card on Hugging Face. The full card is behind the Hugging Face link above.

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