Papers › PEGASUS: Pre-training with Extracted Gap-sentences for Abstractive Summarization

PEGASUS: Pre-training with Extracted Gap-sentences for Abstractive Summarization

18 Dec 2019ICML 2020 1arXiv:1912.08777archive 2025-07-28

Jingqing Zhang, Yao Zhao, Mohammad Saleh, Peter J. Liu

Recent work pre-training Transformers with self-supervised objectives on large text corpora has shown great success when fine-tuned on downstream NLP tasks including text summarization. However, pre-training objectives tailored for abstractive text summarization have not been explored. Furthermore there is a lack of systematic evaluation across diverse domains. In this work, we propose pre-training large Transformer-based encoder-decoder models on massive text corpora with a new self-supervised objective. In PEGASUS, important sentences are removed/masked from an input document and are generated together as one output sequence from the remaining sentences, similar to an extractive summary. We evaluated our best PEGASUS model on 12 downstream summarization tasks spanning news, science, stories, instructions, emails, patents, and legislative bills. Experiments demonstrate it achieves state-of-the-art performance on all 12 downstream datasets measured by ROUGE scores. Our model also shows surprising performance on low-resource summarization, surpassing previous state-of-the-art results on 6 datasets with only 1000 examples. Finally we validated our results using human evaluation and show that our model summaries achieve human performance on multiple datasets.

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google-research/pegasus officialmentioned in papermentioned on GitHubtfApache-2.0 report
ManuMahadevaswamy/PEGASUS mentioned on GitHubtfApache-2.0 report
allenai/open-mds mentioned on GitHubpytorchApache-2.0 report
amiyamandal-dev/pegasus mentioned on GitHubtfApache-2.0 report
bondarchukb/PEGASUS mentioned on GitHubtfApache-2.0 report
google-research/longt5 mentioned on GitHubtf report
huggingface/transformers mentioned on GitHubpytorch report
ibrahim-elsawy/test mentioned on GitHubtf report
jiacheng-xu/text-sum-uncertainty mentioned on GitHubpytorch report
rsin46/pegasus-demo mentioned on GitHubtfApache-2.0 report
rsreetech/PegasusDemo mentioned on GitHubpytorch report

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add_time_signal google-research/pegasus/pegasus/layers/timing.py official repository unverified Apache-2.0 (permissive) · 8262962c9096134b · report
beam_search google-research/pegasus/pegasus/layers/beam_search.py official repository unverified Apache-2.0 (permissive) · f57d0063335e8a9b · report
ids_to_bias google-research/pegasus/pegasus/layers/attention.py official repository unverified Apache-2.0 (permissive) · d527671852cb1888 · report
inplace_update_i google-research/pegasus/pegasus/layers/decoding.py official repository unverified Apache-2.0 (permissive) · dbfe95961072cf4f · report
length_normalization google-research/pegasus/pegasus/layers/beam_search.py official repository unverified Apache-2.0 (permissive) · 3e4b71dc7e938e80 · report
process_logits google-research/pegasus/pegasus/layers/decoding.py official repository unverified Apache-2.0 (permissive) · 748964a1602cc57e · report
split_heads google-research/pegasus/pegasus/layers/attention.py official repository unverified Apache-2.0 (permissive) · 7eb8334d0e01c2d2 · report
stack google-research/pegasus/pegasus/layers/transformer_block.py official repository unverified Apache-2.0 (permissive) · b6ddfdc46c091f09 · report
upper_triangle_bias google-research/pegasus/pegasus/layers/attention.py official repository unverified Apache-2.0 (permissive) · 1d9052e8189c8d31 · report
parse_json_line google-research/longt5/longt5/data/nq_preprocess.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 3df820a3fa7f5f80 · report
add_time_signal amiyamandal-dev/pegasus/pegasus/layers/timing.py community (archive-listed) unverified Apache-2.0 (permissive) · 1137df4f4d6c95ea · report
beam_search amiyamandal-dev/pegasus/pegasus/layers/beam_search.py community (archive-listed) unverified Apache-2.0 (permissive) · e631e67cdf964175 · report
gen_eval_metrics_fn ManuMahadevaswamy/PEGASUS/pegasus/eval/estimator_metrics.py community (archive-listed) unverified Apache-2.0 (permissive) · 6d538a3d4787a4da · report
gen_eval_metrics_fn amiyamandal-dev/pegasus/pegasus/eval/estimator_metrics.py community (archive-listed) unverified Apache-2.0 (permissive) · dda63a05e27da59c · report
ids2str rsin46/pegasus-demo/text_eval.py community (archive-listed) unverified Apache-2.0 (permissive) · b5de54fd00a4cd5d · report
length_normalization amiyamandal-dev/pegasus/pegasus/layers/beam_search.py community (archive-listed) unverified Apache-2.0 (permissive) · 26a1c4bbb2c2b25a · report
pretrain_eval_metrics_fn ManuMahadevaswamy/PEGASUS/pegasus/eval/estimator_metrics.py community (archive-listed) unverified Apache-2.0 (permissive) · 090d5328998234ab · report
pretrain_eval_metrics_fn amiyamandal-dev/pegasus/pegasus/eval/estimator_metrics.py community (archive-listed) unverified Apache-2.0 (permissive) · 72dda61812887b15 · report
process_logits amiyamandal-dev/pegasus/pegasus/layers/decoding.py community (archive-listed) unverified Apache-2.0 (permissive) · b093c178891eb13c · report

Tasks

Abstractive Text SummarizationDecoderText Summarization

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Abstractive Text Summarization AESLC PEGASUS ROUGE-1 37.68 #1 of 2 Archive leaderboard report
Abstractive Text Summarization AESLC PEGASUS ROUGE-2 21.25 #1 of 2 Archive leaderboard report
Abstractive Text Summarization AESLC PEGASUS ROUGE-L 36.51 #1 of 2 Archive leaderboard report
Abstractive Text Summarization CNN / Daily Mail PEGASUS ROUGE-1 44.17 #18 of 53 Archive leaderboard report
Abstractive Text Summarization CNN / Daily Mail PEGASUS ROUGE-2 21.47 #18 of 53 Archive leaderboard report
Abstractive Text Summarization CNN / Daily Mail PEGASUS ROUGE-L 41.11 #18 of 53 Archive leaderboard report
Text Summarization Arxiv HEP-TH citation graph PEGASUS ROUGE-1 44.67 #16 of 28 Archive leaderboard report
Text Summarization GigaWord PEGASUS ROUGE-1 39.12 #15 of 41 Archive leaderboard report
Text Summarization GigaWord PEGASUS ROUGE-2 19.86 #15 of 41 Archive leaderboard report
Text Summarization GigaWord PEGASUS ROUGE-L 36.24 #15 of 41 Archive leaderboard report
Text Summarization Pubmed PEGASUS ROUGE-1 45.09 #18 of 29 Archive leaderboard report
Text Summarization X-Sum PEGASUSLARGE ROUGE-1 47.21 #5 of 18 Archive leaderboard report
Text Summarization X-Sum PEGASUSLARGE ROUGE-2 24.56 #5 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

Introduced by this paper: PEGASUS

PEGASUS

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