Understanding Factual Errors in Summarization: Errors, Summarizers, Datasets, Error Detectors
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Abstract (arXiv)
The propensity of abstractive summarization models to make factual errors has been studied extensively, including design of metrics to detect factual errors and annotation of errors in current systems' outputs. However, the ever-evolving nature of summarization systems, metrics, and annotated benchmarks makes factuality evaluation a moving target, and drawing clear comparisons among metrics has become increasingly difficult. In this work, we aggregate factuality error annotations from nine existing datasets and stratify them according to the underlying summarization model. We compare performance of state-of-the-art factuality metrics, including recent ChatGPT-based metrics, on this stratified benchmark and show that their performance varies significantly across different types of summarization models. Critically, our analysis shows that much of the recent improvement in the factuality detection space has been on summaries from older (pre-Transformer) models instead of more relevant recent summarization models. We further perform a finer-grained analysis per error-type and find similar performance variance across error types for different factuality metrics. Our results show that no one metric is superior in all settings or for all error types, and we provide recommendations for best practices given these insights.
Key facts. Cited by 104 papers in the map (data through 14 Oct 2026). Builds on 43 of its 64 references that are in the map. First posted on arXiv 25 May 2022.
Builds on
43 of 64 references.
References · 43
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31 more
- 2019Text Summarization with Pretrained Encoderscited by 556
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- 2020Asking and Answering Questions to Evaluate the Factual Consistency of Summariescited by 378
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- 2021Understanding Factuality in Abstractive Summarization with FRANK: A Benchmark for Factuality Metricscited by 287
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- 2021QuestEval: Summarization Asks for Fact-based Evaluationcited by 244
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- 2018Bottom-Up Abstractive Summarizationcited by 177
- 2018Fast Abstractive Summarization with Reinforce-Selected Sentence Rewritingcited by 158
- 2021Annotating and Modeling Fine-grained Factuality in Summarizationcited by 131
- 2021Hallucinated but Factual! Inspecting the Factuality of Hallucinations in Abstractive Summarizationcited by 129
- 2020Evaluating Factuality in Generation with Dependency-level Entailmentcited by 122
- 2021CLIFF: Contrastive Learning for Improving Faithfulness and Factuality in Abstractive Summarizationcited by 120
- 2021Entity-level Factual Consistency of Abstractive Text Summarizationcited by 118
- 2020Factual Error Correction for Abstractive Summarization Modelscited by 108
- 2019Optimizing the Factual Correctness of a Summary: A Study of Summarizing Radiology Reportscited by 96
- 2021Improving Faithfulness in Abstractive Summarization with Contrast Candidate Generation and Selectioncited by 76
- 2018Multi-Reward Reinforced Summarization with Saliency and Entailmentcited by 73
- 2020What Have We Achieved on Text Summarization?cited by 65
- 2018Learning to Extract Coherent Summary via Deep Reinforcement Learningcited by 64
- 2018Neural Document Summarization by Jointly Learning to Score and Select Sentencescited by 56
- 2021Improving Factual Consistency of Abstractive Summarization via Question Answeringcited by 55
- 2018A Unified Model for Extractive and Abstractive Summarization using Inconsistency Losscited by 47
- 2018BanditSum: Extractive Summarization as a Contextual Banditcited by 46
- 2021CONFIT: Toward Faithful Dialogue Summarization with Linguistically-Informed Contrastive Fine-tuningcited by 44
- 2021ConvoSumm: Conversation Summarization Benchmark and Improved Abstractive Summarization with Argument Miningcited by 38
- 2018Improving Abstraction in Text Summarizationcited by 35
- 2018Soft Layer-Specific Multi-Task Summarization with Entailment and Question Generationcited by 25
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- 2018Closed-Book Training to Improve Summarization Encoder Memorycited by 6
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Citing papers per year: 2022: 9; 2023: 24; 2024: 37; 2025: 20; 2026: 14.
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- 2025GINGER: Grounded Information Nugget-Based Generation of Responses23 Mar 2025
- 2024FaithBench: A Diverse Hallucination Benchmark for Summarization by Modern LLMs17 Oct 2024
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- 2026Writerslogic at the CLEF 2026 SimpleText Track: Multi-Candidate LLM Simplification and Stacked Complexity Spotting2 Oct 2026
- 2026RAIM: Robust Aggregation of Inexpensive Models for Hallucination Detection30 Sep 2026
- 2026Information Satisfaction: A Reader-Centered Axis for Summarization Evaluation14 Aug 2026
- 2026Explicit, Not Longer: What Makes Epistemic Stance Survive Memory Compression7 Aug 2026
- 2026FACTWASH: Catching AI Rewrites That Wash Hearsay into Fact4 Aug 2026
- 2026Averaging Bias: Human Faithfulness Annotations are not Locally Faithful31 Jul 2026
- 2026Token-Level Off-Policy Learning for Faithful Generation Under Distribution Shift20 Jul 2026
- 2026Layer-Resolved Optimal Transport for Hallucination Detection in NMT and Abstractive Summarization11 Jun 2026
- 2026ThinknCheck: Grounded Claim Verification with Compact, Reasoning-Driven, and Interpretable Models2 Apr 2026
- 2026DIAL-SUMMER: A Structured Evaluation Framework of Hierarchical Errors in Dialogue Summaries8 Feb 2026
- 2025AlignCheck: a Semantic Open-Domain Metric for Factual Consistency Assessment3 Dec 2025
- 2025InforME: Improving Informativeness of Abstractive Text Summarization With Informative Attention Guided by Named Entity Salience7 Oct 2025
12 newest of 81 All 81 (JSON)