Papers › K-Adapter: Infusing Knowledge into Pre-Trained Models with Adapters

K-Adapter: Infusing Knowledge into Pre-Trained Models with Adapters

5 Feb 2020Findings (ACL) 2021 8arXiv:2002.01808archive 2025-07-28

Ruize Wang, Duyu Tang, Nan Duan, Zhongyu Wei, Xuanjing Huang, Jianshu ji, Guihong Cao, Daxin Jiang, Ming Zhou

We study the problem of injecting knowledge into large pre-trained models like BERT and RoBERTa. Existing methods typically update the original parameters of pre-trained models when injecting knowledge. However, when multiple kinds of knowledge are injected, the historically injected knowledge would be flushed away. To address this, we propose K-Adapter, a framework that retains the original parameters of the pre-trained model fixed and supports the development of versatile knowledge-infused model. Taking RoBERTa as the backbone model, K-Adapter has a neural adapter for each kind of infused knowledge, like a plug-in connected to RoBERTa. There is no information flow between different adapters, thus multiple adapters can be efficiently trained in a distributed way. As a case study, we inject two kinds of knowledge in this work, including (1) factual knowledge obtained from automatically aligned text-triplets on Wikipedia and Wikidata and (2) linguistic knowledge obtained via dependency parsing. Results on three knowledge-driven tasks, including relation classification, entity typing, and question answering, demonstrate that each adapter improves the performance and the combination of both adapters brings further improvements. Further analysis indicates that K-Adapter captures versatile knowledge than RoBERTa.

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microsoft/K-Adapter mentioned on GitHubpytorchMIT report
stevekgyang/sccl mentioned on GitHubpytorch report

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swish microsoft/K-Adapter/pytorch_transformers/modeling_bert.py community (archive-listed) ran · our draft was wrong fingerprinted MIT (permissive) · 0f786c407fb1ee4c · report
build_tf_to_pytorch_map microsoft/K-Adapter/pytorch_transformers/modeling_transfo_xl.py community (archive-listed) ran · our draft was wrong MIT (permissive) · 35ef111fc00c21b4 · report
gelu microsoft/K-Adapter/pytorch_transformers/modeling_gpt2.py community (archive-listed) ran · our draft was wrong fingerprinted MIT (permissive) · 8d23fbe2b99b840b · report
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gelu microsoft/K-Adapter/pytorch_transformers/modeling_distilbert.py community (archive-listed) ran fingerprinted MIT (permissive) · 69c6d14de8190cfb · report
load_tf_weights_in_bert microsoft/K-Adapter/pytorch_transformers/modeling_bert.py community (archive-listed) ran · our draft was wrong MIT (permissive) · 0c145728a35789fa · report
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accuracy microsoft/K-Adapter/lin-adapter.py community (archive-listed) unverified MIT (permissive) · 743523b60fbbb166 · report
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get_property2idx_dict microsoft/K-Adapter/fac-adapter.py community (archive-listed) unverified MIT (permissive) · 6b8a0eeef9e90879 · report
load_tf_weights_in_gpt2 microsoft/K-Adapter/pytorch_transformers/modeling_gpt2.py community (archive-listed) unverified MIT (permissive) · 654e91efc679fe84 · report
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Tasks

Dependency ParsingEntity TypingQuestion AnsweringRelation ClassificationRelation Extraction

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Entity Typing Open Entity K-Adapter ( fac-adapter ) F1 77.6916 #1 of 3 Archive leaderboard report
Entity Typing Open Entity K-Adapter ( fac-adapter ) Precision 79.6712 #1 of 3 Archive leaderboard report
Entity Typing Open Entity K-Adapter ( fac-adapter ) Recall 75.8081 #1 of 3 Archive leaderboard report
Entity Typing Open Entity K-Adapter ( fac-adapter + lin-adapter ) F1 77.6127 #2 of 3 Archive leaderboard report
Entity Typing Open Entity K-Adapter ( fac-adapter + lin-adapter ) Precision 78.9956 #2 of 3 Archive leaderboard report
Entity Typing Open Entity K-Adapter ( fac-adapter + lin-adapter ) Recall 76.2774 #2 of 3 Archive leaderboard report
Relation Classification TACRED RoBERTa F1 71.3 #8 of 17 Archive leaderboard report
Relation Classification TACRED K-Adapter F1 72.0 #13 of 17 Archive leaderboard report
Relation Extraction TACRED K-ADAPTER (F+L) F1 72.04 #14 of 40 Archive leaderboard report
Relation Extraction TACRED K-ADAPTER (F+L) F1 (1% Few-Shot) 13.8 #14 of 40 Archive leaderboard report
Relation Extraction TACRED K-ADAPTER (F+L) F1 (10% Few-Shot) 56.0 #14 of 40 Archive leaderboard report
Relation Extraction TACRED K-ADAPTER (F+L) F1 (5% Few-Shot) 45.1 #14 of 40 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

AdamAttentionAttention DropoutBERTDense ConnectionsDropoutLayer NormalizationLinear LayerLinear Warmup With Linear DecayMulti-Head AttentionResidual ConnectionRoBERTaSoftmaxWeight DecayWordPiece

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