One Thousand and One Pairs: A "novel" challenge for long-context language models
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Abstract (arXiv)
Synthetic long-context LLM benchmarks (e.g., "needle-in-the-haystack") test only surface-level retrieval capabilities, but how well can long-context LLMs retrieve, synthesize, and reason over information across book-length inputs? We address this question by creating NoCha, a dataset of 1,001 minimally different pairs of true and false claims about 67 recently-published English fictional books, written by human readers of those books. In contrast to existing long-context benchmarks, our annotators confirm that the largest share of pairs in NoCha require global reasoning over the entire book to verify. Our experiments show that while human readers easily perform this task, it is enormously challenging for all ten long-context LLMs that we evaluate: no open-weight model performs above random chance (despite their strong performance on synthetic benchmarks), while GPT-4o achieves the highest accuracy at 55.8%. Further analysis reveals that (1) on average, models perform much better on pairs that require only sentence-level retrieval vs. global reasoning; (2) model-generated explanations for their decisions are often inaccurate even for correctly-labeled claims; and (3) models perform substantially worse on speculative fiction books that contain extensive world-building. The methodology proposed in NoCha allows for the evolution of the benchmark dataset and the easy analysis of future models.
Key facts. Cited by 80 papers in the map (data through 7 Oct 2026). Builds on 31 of its 66 references that are in the map. First posted on arXiv 24 Jun 2024.
Builds on
31 of 66 references.
References · 31
- 2023Lost in the Middle: How Language Models Use Long Contextscited by 3,383
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- 2018FEVER: a large-scale dataset for Fact Extraction and VERificationcited by 1,362
- 2024RULER: What's the Real Context Size of Your Long-Context Language Models?cited by 1,270
- 2023FActScore: Fine-grained Atomic Evaluation of Factual Precision in Long Form Text Generationcited by 1,259
- 2020How Much Knowledge Can You Pack Into the Parameters of a Language Model?cited by 713
- 2020Long Range Arena: A Benchmark for Efficient Transformerscited by 696
- 2019BLiMP: The Benchmark of Linguistic Minimal Pairs for Englishcited by 553
- 2020Fact or Fiction: Verifying Scientific Claimscited by 546
- 2021SummaC: Re-Visiting NLI-based Models for Inconsistency Detection in Summarizationcited by 402
19 more
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- 2024Long-context LLMs Struggle with Long In-context Learningcited by 285
- 2021QAFactEval: Improved QA-Based Factual Consistency Evaluation for Summarizationcited by 233
- 2023L-Eval: Instituting Standardized Evaluation for Long Context Language Modelscited by 232
- 2024Leak, Cheat, Repeat: Data Contamination and Evaluation Malpractices in Closed-Source LLMscited by 224
- 2021Get Your Vitamin C! Robust Fact Verification with Contrastive Evidencecited by 222
- 2023ZeroSCROLLS: A Zero-Shot Benchmark for Long Text Understandingcited by 175
- 2024Long-form factuality in large language modelscited by 146
- 2023Stop Uploading Test Data in Plain Text: Practical Strategies for Mitigating Data Contamination by Evaluation Benchmarkscited by 139
- 2023Focused Transformer: Contrastive Training for Context Scalingcited by 133
- 2023Speak, Memory: An Archaeology of Books Known to ChatGPT/GPT-4cited by 123
- 2021Do Long-Range Language Models Actually Use Long-Range Context?cited by 92
- 2024FABLES: Evaluating faithfulness and content selection in book-length summarizationcited by 65
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- 2022MuLD: The Multitask Long Document Benchmarkcited by 9
- 2021Perhaps PTLMs Should Go to School -- A Task to Assess Open Book and Closed Book QAcited by 8
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Citing papers per year: 2024: 19; 2025: 45; 2026: 16.
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