Factual Dialogue Summarization via Learning from Large Language Models
Paper · 2025 · Rongxin Zhu, Jey Han Lau and Jianzhong Qi
Summary
Smaller pretrained summarizers often produce dialogue summaries that contain facts not supported by the conversation. Large LLMs are more faithful, but they can be impractical because of compute cost and privacy concerns. The authors transfer this ability through symbolic knowledge distillation. They used gpt-3.5-turbo as a black-box teacher. For each dialogue, it first wrote faithful summaries, then rewrote each one to contain subtle factual mistakes and explained those errors. The resulting positive and negative texts trained student models (BART, PEGASUS, Flan-T5) on SAMSum and DialogSum. Training used three strategies: plain sequence-level distillation and two contrastive objectives. These students outperformed strong baselines such as FactPEGASUS and SWING, which depend on elaborate rule-based negative-sample construction. Fluency, coherence and relevance were preserved according to both automatic metrics and human judges. The best configuration, Flan-T5 with PairContrast, roughly matched human reference summaries in faithfulness and was rated more informative. Compact, deployable dialogue summarizers can therefore inherit factuality from proprietary LLMs without access to their output probabilities.
Key points
- The teacher (ChatGPT, gpt-3.5-turbo) generated k = 3 consistent summaries per dialogue, plus one corrupted version of each. Asking the teacher to explain its inserted errors yielded better negatives.
- Three training variants were compared against MLE: SeqDistill, PairContrast and MarginContrast. They were tested on BART, PEGASUS and Flan-T5 using the SAMSum and DialogSum datasets.
- The distilled models write longer summaries than the terse human references. This explains their noticeably lower ROUGE despite higher faithfulness, measured with metrics such as AlignScore.
- In a SAMSum example, AlignScore was 0.980 for MarginContrast and 0.963 for PairContrast. By comparison, the human reference scored 0.907, SWING 0.888 and FactPEGASUS 0.623.
- Stated limitations:
- Only one teacher LLM was used.
- The data consists solely of short everyday dialogues.
- The teacher may have seen the test sets during training.
- Students may inherit the teacher's biases.
- API costs grow with data volume.
- Data and code are released on GitHub (731935354/symbolic_distill_contrastive_summ).
Institutions
Fields, topics and concepts
📚 Shelves 4The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 worksArts and Humanities · 16,039 worksLanguage and Linguistics · 15,891 works
🧭 Topics 3Research subjects and languages the work is about.Language models & pretraining · 3,320 worksDialogue systems · 624 worksSummarization · 232 works
Cite
Cite as Rongxin Zhu, Jey Han Lau and Jianzhong Qi. 2025. Factual Dialogue Summarization via Learning from Large Language Models. Proceedings of the 31st International Conference on Computational Linguistics.
@inproceedings{zhu2025factual,
title = {{Factual Dialogue Summarization via Learning from Large Language Models}},
author = {Rongxin Zhu, Jey Han Lau and Jianzhong Qi},
booktitle = {Proceedings of the 31st International Conference on Computational Linguistics},
year = {2025},
url = {https://aclanthology.org/2025.coling-main.302/}
}References
- Griffin Adams, Han-Chin Shing, Qing Sun, Christopher Winestock, Kathleen Mckeown, and Noémie Elhadad. 2022. Learning to revise references for faithful summarization. In Findings of the Association for Computational Linguistics: EMNLP 2022, pages 4009–4027. find
- Gustavo Aguilar, Yuan Ling, Yu Zhang, Benjamin Yao, Xing Fan, and Chenlei Guo. 2020. Knowledge distillation from internal representations. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 34, pages 7350–7357. find
- Vidhisha Balachandran, Hannaneh Hajishirzi, William Cohen, and Yulia Tsvetkov. 2022. Correcting diverse factual errors in abstractive summarization via post-editing and language model infilling. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 9818–983… find
- Tom Brown, Benjamin Mann, Nick Ryder, Melanie Subbiah, Jared D Kaplan, Prafulla Dhariwal, Arvind Neelakantan, Pranav Shyam, Girish Sastry, Amanda Askell, et al. 2020. Language models are few-shot learners. Advances in neural information processing systems, 33:1877–1901.
- Shuyang Cao and Lu Wang. 2021. Cliff: Contrastive learning for improving faithfulness and factuality in abstractive summarization. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 6633–6649.
- Sihao Chen, Fan Zhang, Kazoo Sone, and Dan Roth. 2021a. Improving faithfulness in abstractive summarization with contrast candidate generation and selection. In Proceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technolog…
- Yulong Chen, Yang Liu, Liang Chen, and Yue Zhang. 2021b. Dialogsum: A real-life scenario dialogue summarization dataset. In Findings of the Association for Computational Linguistics: ACL-IJCNLP 2021, pages 5062–5074.
- Hyung Won Chung, Le Hou, Shayne Longpre, Barret Zoph, Yi Tay, William Fedus, Yunxuan Li, Xuezhi Wang, Mostafa Dehghani, Siddhartha Brahma, et al. 2024. Scaling instruction-finetuned language models. Journal of Machine Learning Research, 25(70):1–53. find
- Mingkai Deng, Bowen Tan, Zhengzhong Liu, Eric Xing, and Zhiting Hu. 2021. Compression, transduction, and creation: A unified framework for evaluating natural language generation. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 7580–7605.
- Esin Durmus, He He, and Mona Diab. 2020. FEQA: A question answering evaluation framework for faithfulness assessment in abstractive summarization. In Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 5055– 5070, Online. Association for Computational Lingu…
- Alexander Fabbri, Chien-Sheng Wu, Wenhao Liu, and Caiming Xiong. 2022. QAFactEval: Improved QA-based factual consistency evaluation for summarization. In Proceedings of the 2022 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, pa…
- Jinlan Fu, See-Kiong Ng, Zhengbao Jiang, and Pengfei Liu. 2023. Gptscore: Evaluate as you desire. arXiv preprint arXiv:2302.04166. find
- Saadia Gabriel, Asli Celikyilmaz, Rahul Jha, Yejin Choi, and Jianfeng Gao. 2021. Go figure: A meta evaluation of factuality in summarization. In Findings of the Association for Computational Linguistics: ACL-IJCNLP 2021, pages 478–487.
- Bogdan Gliwa, Iwona Mochol, Maciej Biesek, and Aleksander Wawer. 2019a. Samsum corpus: A human-annotated dialogue dataset for abstractive summarization.
- EMNLP-IJCNLP 2019, page 70. find
- Bogdan Gliwa, Iwona Mochol, Maciej Biesek, and Aleksander Wawer. 2019b. SAMSum corpus: A human-annotated dialogue dataset for abstractive summarization. In Proceedings of the 2nd Workshop on New Frontiers in Summarization, pages 70–79, Hong Kong, China. Association for Computational Linguistics.
- Tanya Goyal and Greg Durrett. 2020. Evaluating factuality in generation with dependency-level entailment. In Findings of the Association for Computational Linguistics: EMNLP 2020, pages 3592–3603, Online. Association for Computational Linguistics.
- Tanya Goyal and Greg Durrett. 2021. Annotating and modeling fine-grained factuality in summarization. In Proceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, pages 1449–1462.
- Yuxian Gu, Li Dong, Furu Wei, and Minlie Huang. 2024. Minillm: Knowledge distillation of large language models. In The Twelfth International Conference on Learning Representations. find
- Geoffrey Hinton, Oriol Vinyals, and Jeff Dean. 2015. Distilling the knowledge in a neural network. arXiv preprint arXiv:1503.02531.
- Kung-Hsiang Huang, Siffi Singh, Xiaofei Ma, Wei Xiao, Feng Nan, Nicholas Dingwall, William Yang Wang, and Kathleen Mckeown. 2023. Swing: Balancing coverage and faithfulness for dialogue summarization. In Findings of the Association for Computational Linguistics: EACL 2023, pages 512–525. find
- Luyang Huang, Lingfei Wu, and Lu Wang. 2020. Knowledge graph-augmented abstractive summarization with semantic-driven cloze reward. In Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 5094–5107. find
- Yichong Huang, Xiachong Feng, Xiaocheng Feng, and Bing Qin. 2021. The factual inconsistency problem in abstractive text summarization: A survey. arXiv preprint arXiv:2104.14839. — [arXiv:2104.14839](https://arxiv.org/abs/2104.14839) find
- Pengcheng Jiang, Cao Xiao, Zifeng Wang, Parminder Bhatia, Jimeng Sun, and Jiawei Han. 2024. Trisum: Learning summarization ability from large language models with structured rationale. arXiv preprint arXiv:2403.10351. find
- Jaehun Jung, Ximing Lu, Liwei Jiang, Faeze Brahman, Peter West, Pang Wei Koh, and Yejin Choi. 2024. Information-theoretic distillation for reference-less summarization. arXiv preprint arXiv:2403.13780. find
- Yoon Kim and Alexander M Rush. 2016. Sequence-level knowledge distillation. In Proceedings of the 2016 Conference on Empirical Methods in Natural Language Processing, pages 1317–1327.
- Yang Liu, Dan Iter, Yichong Xu, Shuohang Wang, Ruochen Xu, and Chenguang Zhu. 2023a. G-eval: NLG evaluation using gpt-4 with better human alignment. In Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing, pages 2511–2522, Singapore. Association for Computational Li…
- Yang Liu, Dan Iter, Yichong Xu, Shuohang Wang, Ruochen Xu, and Chenguang Zhu. 2023b. Gpteval: Nlg evaluation using gpt-4 with better human alignment. arXiv preprint arXiv:2303.16634.
- Yixin Liu, Alexander R Fabbri, Pengfei Liu, Dragomir Radev, and Arman Cohan. 2023c. On learning to summarize with large language models as references. arXiv preprint arXiv:2305.14239.
- Yixin Liu and Pengfei Liu. 2021. Simcls: A simple framework for contrastive learning of abstractive summarization. In Proceedings of the 59th Annual Meeting of the Association for Computational Linguistics and the 11th International Joint Conference on Natural Language Processing (Volume 2: Short Pa…
- Wojciech Kryscinski, Bryan McCann, Caiming Xiong, and Richard Socher. 2020. Evaluating the factual consistency of abstractive text summarization. In Proceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP), pages 9332–9346, Online. Association for Computational…
- Potsawee Manakul, Adian Liusie, and Mark Gales. 2023. Mqag: Multiple-choice question answering and generation for assessing information consistency in summarization. In Proceedings of the 13th International Joint Conference on Natural Language Processing and the 3rd Conference of the Asia-Pacific Ch… find
- Philippe Laban, Tobias Schnabel, Paul N Bennett, and Marti A Hearst. 2022. Summac: Re-visiting nli-based models for inconsistency detection in summarization. Transactions of the Association for Computational Linguistics, 10:163–177. find
- Joshua Maynez, Shashi Narayan, Bernd Bohnet, and Ryan McDonald. 2020. On faithfulness and factuality in abstractive summarization. In Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 1906–1919.
- Hwanhee Lee, Cheoneum Park, Seunghyun Yoon, Trung Bui, Franck Dernoncourt, Juae Kim, and Kyomin Jung. 2022. Factual error correction for abstractive summaries using entity retrieval. In Proceedings of the 2nd Workshop on Natural Language Generation, Evaluation, and Metrics (GEM), pages 439–444. find
- Sewon Min, Kalpesh Krishna, Xinxi Lyu, Mike Lewis, Wen-tau Yih, Pang Wei Koh, Mohit Iyyer, Luke Zettlemoyer, and Hannaneh Hajishirzi. 2023. Factscore: Fine-grained atomic evaluation of factual precision in long form text generation. arXiv preprint arXiv:2305.14251.
- Mike Lewis, Yinhan Liu, Naman Goyal, Marjan Ghazvininejad, Abdelrahman Mohamed, Omer Levy, Veselin Stoyanov, and Luke Zettlemoyer. 2020. Bart: Denoising sequence-to-sequence pre-training for natural language generation, translation, and comprehension. In Proceedings of the 58th Annual Meeting of the…
- Chin-Yew Lin. 2004. Rouge: A package for automatic evaluation of summaries. In Text summarization branches out, pages 74–81.
- Wei Liu, Huanqin Wu, Wenjing Mu, Zhen Li, Tao Chen, and Dan Nie. 2021. Co2sum: contrastive learning for factual-consistent abstractive summarization. arXiv preprint arXiv:2112.01147. — [arXiv:2112.01147](https://arxiv.org/abs/2112.01147) find
- Sewon Min, Xinxi Lyu, Ari Holtzman, Mikel Artetxe, Mike Lewis, Hannaneh Hajishirzi, and Luke Zettlemoyer. 2022. Rethinking the role of demonstrations: What makes in-context learning work? In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 11048–11064.
- Feng Nan, Ramesh Nallapati, Zhiguo Wang, Cicero dos Santos, Henghui Zhu, Dejiao Zhang, Kathleen Mckeown, and Bing Xiang. 2021. Entity-level factual consistency of abstractive text summarization. In Proceedings of the 16th Conference of the European Chapter of the Association for Computational Lingui…
- Long Ouyang, Jeffrey Wu, Xu Jiang, Diogo Almeida, Carroll Wainwright, Pamela Mishkin, Chong Zhang, Sandhini Agarwal, Katarina Slama, Alex Ray, et al. 2022. Training language models to follow instructions with human feedback. Advances in Neural Information Processing Systems, 35:27730–27744.
- Maarten Sap, Ronan Le Bras, Emily Allaway, Chandra Bhagavatula, Nicholas Lourie, Hannah Rashkin, Brendan Roof, Noah A Smith, and Yejin Choi. 2019. Atomic: An atlas of machine commonsense for if-then reasoning. In Proceedings of the AAAI conference on artificial intelligence, volume 33, pages 3027–30… find
- Thomas Scialom, Paul-Alexis Dray, Sylvain Lamprier, Benjamin Piwowarski, Jacopo Staiano, Alex Wang, and Patrick Gallinari. 2021. QuestEval: Summarization asks for fact-based evaluation. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 6594–6604, Online…
- Melanie Sclar, Peter West, Sachin Kumar, Yulia Tsvetkov, and Yejin Choi. 2022. Referee: Reference-free sentence summarization with sharper controllability through symbolic knowledge distillation. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 9649–96… find
- Hwanjun Song, Igor Shalyminov, Hang Su, Siffi Singh, Kaisheng Yao, and Saab Mansour. 2023. Enhancing abstractiveness of summarization models through calibrated distillation. In Findings of the Association for Computational Linguistics: EMNLP 2023, pages 7026–7036. find
- Emma Strubell, Ananya Ganesh, and Andrew McCallum. 2019. Energy and policy considerations for deep learning in nlp. In Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics. Association for Computational Linguistics.
- Zhiqing Sun, Hongkun Yu, Xiaodan Song, Renjie Liu, Yiming Yang, and Denny Zhou. 2020. Mobilebert: a compact task-agnostic bert for resource-limited devices. In Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 2158–2170.
- David Wan and Mohit Bansal. 2022a. Factpegasus: Factuality-aware pre-training and fine-tuning for abstractive summarization. In Proceedings of the 2022 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, pages 1010–1028.
- David Wan and Mohit Bansal. 2022b. FactPEGASUS: Factuality-aware pre-training and fine-tuning for abstractive summarization. In Proceedings of the 2022 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, pages 1010–1028, Seattle, Un…
- Bin Wang, Chen Zhang, Yan Zhang, Yiming Chen, and Haizhou Li. 2022a. Analyzing and evaluating faithfulness in dialogue summarization. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 4897–4908. find
- Tianshu Wang, Faisal Ladhak, Esin Durmus, and He He. 2022b. Improving faithfulness by augmenting negative summaries from fake documents. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 11913–11921. find
- Jason Wei, Maarten Bosma, Vincent Zhao, Kelvin Guu, Adams Wei Yu, Brian Lester, Nan Du, Andrew M Dai, and Quoc V Le. 2021. Finetuned language models are zero-shot learners. In International Conference on Learning Representations.
- Jason Wei, Yi Tay, Rishi Bommasani, Colin Raffel, Barret Zoph, Sebastian Borgeaud, Dani Yogatama, Maarten Bosma, Denny Zhou, Donald Metzler, et al. 2022. Emergent abilities of large language models. Transactions on Machine Learning Research.
- Peter West, Chandra Bhagavatula, Jack Hessel, Jena Hwang, Liwei Jiang, Ronan Le Bras, Ximing Lu, Sean Welleck, and Yejin Choi. 2022. Symbolic knowledge distillation: from general language models to commonsense models. In Proceedings of the 2022 Conference of the North American Chapter of the Associa…
- Qinyuan Ye, Bill Yuchen Lin, and Xiang Ren. 2021. Crossfit: A few-shot learning challenge for cross-task generalization in nlp. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 7163–7189. find
- Weizhe Yuan, Graham Neubig, and Pengfei Liu. 2021. Bartscore: Evaluating generated text as text generation. Advances in Neural Information Processing Systems, 34:27263–27277.
- Yuheng Zha, Yichi Yang, Ruichen Li, and Zhiting Hu. 2023a. AlignScore: Evaluating factual consistency with a unified alignment function. In Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 11328–11348, Toronto, Canada. Association…
- Yuheng Zha, Yichi Yang, Ruichen Li, and Zhiting Hu. 2023b. Alignscore: Evaluating factual consistency with a unified alignment function. In Annual Meeting of the Association for Computational Linguistics.
- Huajian Zhang, Yumo Xu, and Laura Perez-Beltrachini. 2024. Fine-grained natural language inference based faithfulness evaluation for diverse summarisation tasks. In Conference of the European Chapter of the Association for Computational Linguistics. find
- Jingqing Zhang, Yao Zhao, Mohammad Saleh, and Peter Liu. 2020. Pegasus: Pre-training with extracted gap-sentences for abstractive summarization. In International Conference on Machine Learning, pages 11328–11339. PMLR. model gpt-3.5-turbo, validating that these summaries are mostly factually consist…
- Tianyi Zhang, Faisal Ladhak, Esin Durmus, Percy Liang, Kathleen McKeown, and Tatsunori B Hashimoto. 2023. Benchmarking large language models for news summarization. arXiv preprint arXiv:2301.13848.
- Yao Zhao, Mikhail Khalman, Rishabh Joshi, Shashi Narayan, Mohammad Saleh, and Peter J Liu. 2022. Calibrating sequence likelihood improves conditional language generation. In The Eleventh International Conference on Learning Representations. find
- Ming Zhong, Yang Liu, Da Yin, Yuning Mao, Yizhu Jiao, Peng Liu, Chenguang Zhu, Heng Ji, and Jiawei Han. 2022a. Towards a unified multi-dimensional evaluator for text generation. In Conference on Empirical Methods in Natural Language Processing.
- Ming Zhong, Yang Liu, Da Yin, Yuning Mao, Yizhu Jiao, Pengfei Liu, Chenguang Zhu, Heng Ji, and Jiawei Han. 2022b. Towards a unified multi-dimensional evaluator for text generation. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 2023– 2038.
- Chenguang Zhu, William Hinthorn, Ruochen Xu, Qingkai Zeng, Michael Zeng, Xuedong Huang, and Meng Jiang. 2021. Enhancing factual consistency of abstractive summarization. In Proceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Langua…
- Rongxin Zhu, Jianzhong Qi, and Jey Han Lau. 2023. Annotating and detecting fine-grained factual errors for dialogue summarization. In Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 6825–6845. find
Updated
This page in Markdown → https://md.research.elamur.ai/free/en/papers/zhu-2025-factual-dialogue-summarization-learning-large/