Papers › SimCLS: A Simple Framework for Contrastive Learning of Abstractive Summarization

SimCLS: A Simple Framework for Contrastive Learning of Abstractive Summarization

3 Jun 2021ACL 2021 5arXiv:2106.01890archive 2025-07-28

Yixin Liu, PengFei Liu

In this paper, we present a conceptually simple while empirically powerful framework for abstractive summarization, SimCLS, which can bridge the gap between the learning objective and evaluation metrics resulting from the currently dominated sequence-to-sequence learning framework by formulating text generation as a reference-free evaluation problem (i.e., quality estimation) assisted by contrastive learning. Experimental results show that, with minor modification over existing top-scoring systems, SimCLS can improve the performance of existing top-performing models by a large margin. Particularly, 2.51 absolute improvement against BART and 2.50 over PEGASUS w.r.t ROUGE-1 on the CNN/DailyMail dataset, driving the state-of-the-art performance to a new level. We have open-sourced our codes and results: https://github.com/yixinL7/SimCLS. Results of our proposed models have been deployed into ExplainaBoard platform, which allows researchers to understand our systems in a more fine-grained way.

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yixinL7/SimCLS officialmentioned in paperpytorch report
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ReRanker yixinL7/SimCLS/model.py official repository ran no licence file found · pointer only · f443e33ff3e904b7 · report
CandidateGenerator andrejmiscic/simcls-pytorch/src/model.py community (archive-listed) ran fingerprinted MIT (permissive) · c7db94543f6a5470 · report
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SimCLS andrejmiscic/simcls-pytorch/src/model.py community (archive-listed) unverified MIT (permissive) · f0aec9ce53303b48 · report

Tasks

Abstractive Text SummarizationContrastive LearningText GenerationText Summarization

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Abstractive Text Summarization CNN / Daily Mail BART + SimCLS ROUGE-1 46.67 #6 of 53 Archive leaderboard report
Abstractive Text Summarization CNN / Daily Mail BART + SimCLS ROUGE-2 22.15 #6 of 53 Archive leaderboard report
Abstractive Text Summarization CNN / Daily Mail BART + SimCLS ROUGE-L 43.54 #6 of 53 Archive leaderboard report
Text Summarization X-Sum PEGASUS + SimCLS ROUGE-1 47.61 #4 of 18 Archive leaderboard report
Text Summarization X-Sum PEGASUS + SimCLS ROUGE-2 24.57 #4 of 18 Archive leaderboard report
Text Summarization X-Sum PEGASUS + SimCLS ROUGE-L 39.44 #4 of 18 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

AdamAttentionBARTBPEDense ConnectionsDropoutLayer NormalizationLinear LayerMulti-Head AttentionPEGASUSResidual ConnectionSoftmax

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