Unsupervised Summarization Re-ranking

Mathieu Ravaut, Shafiq Joty, Nancy Chen


Abstract
With the rise of task-specific pre-training objectives, abstractive summarization models like PEGASUS offer appealing zero-shot performance on downstream summarization tasks. However, the performance of such unsupervised models still lags significantly behind their supervised counterparts. Similarly to the supervised setup, we notice a very high variance in quality among summary candidates from these models while only one candidate is kept as the summary output. In this paper, we propose to re-rank summary candidates in an unsupervised manner, aiming to close the performance gap between unsupervised and supervised models. Our approach improves the unsupervised PEGASUS by up to 7.27% and ChatGPT by up to 6.86% relative mean ROUGE across four widely-adopted summarization benchmarks ; and achieves relative gains of 7.51% (up to 23.73% from XSum to WikiHow) averaged over 30 zero-shot transfer setups (finetuning on a dataset, evaluating on another).
Anthology ID:
2023.findings-acl.529
Volume:
Findings of the Association for Computational Linguistics: ACL 2023
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Anna Rogers, Jordan Boyd-Graber, Naoaki Okazaki
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
8341–8376
Language:
URL:
https://aclanthology.org/2023.findings-acl.529
DOI:
10.18653/v1/2023.findings-acl.529
Bibkey:
Cite (ACL):
Mathieu Ravaut, Shafiq Joty, and Nancy Chen. 2023. Unsupervised Summarization Re-ranking. In Findings of the Association for Computational Linguistics: ACL 2023, pages 8341–8376, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Unsupervised Summarization Re-ranking (Ravaut et al., Findings 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.findings-acl.529.pdf