Pointwise Mutual Information as a Performance Gauge for Retrieval-Augmented Generation
On the map: Retrieval-augmented generation → RAG robustness and adaptive retrieval
Abstract (arXiv)
Recent work suggests that large language models enhanced with retrieval-augmented generation are easily influenced by the order, in which the retrieved documents are presented to the model when solving tasks such as question answering (QA). However, there is no method to date that exploits this phenomenon to improve generation. We fill this gap. In this study, we show that the pointwise mutual information between a context and a question is an effective gauge for language model performance. Importantly, this gauge does not depend on knowing the answer to the question a priori. Through experiments on two question-answering datasets and a variety of large language models, we find evidence for an empirical correlation between answer accuracy and pointwise mutual information. Additionally, we propose two methods that use the pointwise mutual information between a document and a question as a gauge for selecting and constructing prompts that lead to better performance, whose effectiveness we demonstrate through experimentation.
Key facts. Cited by 6 papers in the map (data through 7 Oct 2026). Placed in RAG robustness and adaptive retrieval, one of 15 directions in Retrieval-augmented generation. Builds on 26 of its 34 references that are in the map. First posted on arXiv 12 Nov 2024.
Builds on
26 of 34 references.
References · 26
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14 more
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Built on by
Citing papers per year: 2025: 4; 2026: 2.
6 papers.
- 2025TinyAlign: Boosting Lightweight Vision-Language Models by Mitigating Modal Alignment Bottleneckscited by 4
- 2026Memory Retrieval for Changing Preferencescited by 3
- 2026Revisiting RAG Retrievers: An Information Theoretic Benchmarkcited by 2
- 2025Graph of Agents: Principled Long Context Modeling by Emergent Multi-Agent Collaborationcited by 1
- 2025Directed Information γ-covering: An Information-Theoretic Framework for Context Engineeringcited by 1
- 2025Grounding Long-Context Reasoning with Contextual Normalization for Retrieval-Augmented Generationcited by 1
- 2026Memory Retrieval for Changing Preferences2 Jun 2026
- 2026Revisiting RAG Retrievers: An Information Theoretic Benchmark25 Feb 2026
- 2025Grounding Long-Context Reasoning with Contextual Normalization for Retrieval-Augmented Generation15 Oct 2025
- 2025Directed Information γ-covering: An Information-Theoretic Framework for Context Engineering30 Sep 2025
- 2025Graph of Agents: Principled Long Context Modeling by Emergent Multi-Agent Collaboration26 Sep 2025
- 2025TinyAlign: Boosting Lightweight Vision-Language Models by Mitigating Modal Alignment Bottlenecks19 May 2025
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- 2024From RAGs to rich parameters: Probing how language models utilize external knowledge over parametric information for factual queries
- 2024Quantifying reliance on external information over parametric knowledge during Retrieval Augmented Generation (RAG) using mechanistic analysis
- 2025Adaptive Retrieval Without Self-Knowledge? Bringing Uncertainty Back Home
- 2025LLM-Specific Utility for Retrieval-Augmented Generation
- 2025Retrieval Augmented Question Answering: When Should LLMs Admit Ignorance?
- 2023Modeling Uncertainty and Using Post-fusion as Fallback Improves Retrieval Augmented Generation with LLMs
- 2026Predicting the Benefit of Retrieval Augmentation in Open-Domain Question Answering
- 2023Retrieval-Generation Synergy Augmented Large Language Models