Cited by 100Topic ModelingAdvanced Text Analysis TechniquesNatural Language Processing Techniques

Reducing Quantity Hallucinations in Abstractive Summarization

Open access
Zhao, Zheng, Cohen, Shay B., Webber, Bonnie·2020·Findings of the Association for Computational Linguistics: EMNLP 2020

Abstract

It is well-known that abstractive summaries are subject to hallucination---including material that is not supported by the original text. While summaries can be made hallucination-free by limiting them to general phrases, such summaries would fail to be very informative. Alternatively, one can try to avoid hallucinations by verifying that any specific entities in the summary appear in the original text in a similar context. This is the approach taken by our system, Herman. The system learns to recognize and verify quantity entities (dates, numbers, sums of money, etc.) in a beam-worth of abstractive summaries produced by state-of-the-art models, in order to up-rank those summaries whose quantity terms are supported by the original text. Experimental results demonstrate that the ROUGE scores of such up-ranked summaries have a higher Precision than summaries that have not been up-ranked, without a comparable loss in Recall, resulting in higher F$_1$. Preliminary human evaluation of up-ranked vs. original summaries shows people's preference for the former.

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Crossref · 10.18653/v1/2020.findings-emnlp.203

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  • Autoregressive generation for abstractive compression is slow and may produce hallucinated content.

    “However, this autoregressive generation process is slow and it may produce hallucinated content (Zhao et al., 2020).”

    From LLMLingua-2: Data Distillation for Efficient and Faithful Task-Agnostic Prompt Compression (2024) · cites this paper as Zhao et al., 2020

    The Abstract (p. 1) and Introduction (p. 1) state that abstractive summaries can contain hallucinated facts. The paper does not state that autoregressive generation is slow; searches for generation speed, latency, and inference time did not establish that part of the claim. (LLM, conf=0.88)

    Experimental — accuracy not yet measured
  • The correctness of numerals in generated text, such as date, quantities and scalars, is important for readers.

    “However, the correctness of numerals in generated text, such as date, quantities and scalars are important for readers [246, 315, 321].”

    From Survey of Hallucination in Natural Language Generation (2023) · cites this paper as [321]

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3 of the 42 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. Dzmitry Bahdanau, Kyunghyun Cho, and Yoshua Bengio. 2015b. Neural machine translation by jointly learning to align and translate. In 3rd International Conference on Learning Representations, ICLR 2015, San Diego, CA, USA, May 7-9, 2015, Conference Track Proceedings .
  2. Shashi Narayan, Shay B. Cohen, and Mirella Lapata. 2018b. Ranking sentences for extractive summarization with reinforcement learning. In Proceedings of the 2018 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long Papers) , pages 1747-1759, New Orleans, Louisiana. Association for Computational Linguistics.
  3. Abigail See, Peter J. Liu, and Christopher D. Manning. 2017. Get to the point: Summarization with pointergenerator networks. In Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers) , pages 10731083, Vancouver, Canada. Association for Computational Linguistics.

Cited by

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Authors
Zhao, Z., Cohen, S. B., & Webber, B.
Affiliations
University of Edinburgh (GB)
Venue
Findings of the Association for Computational Linguistics: EMNLP 2020
Published
2020
Pages
2237-2249
OpenAlex
W3099474967
Cited by
99
References
42
Citations by year
2026: 3 · 2025: 11 · 2024: 10 · 2023: 28 · 2022: 25 · 2021: 22
FWCI
7.16
Type
conference paper
Language
en
Open access
Licence
cc-by
Locations
  • Findings of the Association for Computational Linguistics: EMNLP (Findings of EMNLP) (publishedVersion, cc-by)
  • arXiv (Cornell University) (submittedVersion)
  • arXiv (Cornell University)
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Topic Modeling
  • Physical Sciences › Computer Science › Artificial Intelligence › Advanced Text Analysis Techniques
  • Physical Sciences › Computer Science › Artificial Intelligence › Natural Language Processing Techniques
Keywords
hallucination mitigation, abstractive summarization, beam search, human evaluation of summaries

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