PRMBench: A Fine-grained and Challenging Benchmark for Process-Level Reward Models
On the map: LLM reasoning → Reinforcement learning for reasoning
Abstract (arXiv)
Process-level Reward Models (PRMs) are crucial for complex reasoning and decision-making tasks, where each intermediate step plays an important role in the reasoning process. Since language models are prone to various types of errors during the reasoning process, PRMs are required to possess nuanced capabilities for detecting various implicit error types in real-world scenarios. However, current benchmarks primarily focus on step correctness, failing to evaluate PRMs' performance systematically. To address this gap, we introduce PRMBench, a process-level benchmark specifically designed to assess the fine-grained error detection capabilities of PRMs. PRMBench comprises 6,216 carefully designed problems and 83,456 step-level labels, evaluating models across multiple dimensions, including simplicity, soundness, and sensitivity. In our experiments on 15 models, spanning both open-source PRMs and closed-source large language models prompted as critic models, we uncover significant weaknesses in current PRMs. These findings underscore the challenges inherent in process-level evaluation and highlight key directions for future research. We hope PRMBench can be a robust bench for advancing research on PRM evaluation and development.
Key facts. Cited by 98 papers in the map (data through 7 Oct 2026). Placed in Reinforcement learning for reasoning, one of 17 directions in LLM reasoning. Builds on 30 of its 53 references that are in the map. First posted on arXiv 6 Jan 2025.
Builds on
30 of 53 references.
Closest ancestors · 5
Same direction, newest first
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- 2023Math-Shepherd: Verify and Reinforce LLMs Step-by-step without Human Annotations14 Dec
- 2023Let's Verify Step by Step31 May
- 2022Solving math word problems with process- and outcome-based feedback25 Nov
Other references · 25
- 2021Training Verifiers to Solve Math Word Problemscited by 9,743
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- 2024Qwen2.5-Math Technical Report: Toward Mathematical Expert Model via Self-Improvementcited by 1,057
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- 2023Evaluating Large Language Models at Evaluating Instruction Followingcited by 290
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- 2024O1 Replication Journey: A Strategic Progress Report -- Part 1cited by 140
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- 2024Critic-V: VLM Critics Help Catch VLM Errors in Multimodal Reasoningcited by 50
- 2024Is Your Model Really A Good Math Reasoner? Evaluating Mathematical Reasoning with Checklistcited by 48
- 2024Evaluating Mathematical Reasoning of Large Language Models: A Focus on Error Identification and Correctioncited by 45
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- 2024ErrorRadar: Benchmarking Complex Mathematical Reasoning of Multimodal Large Language Models Via Error Detectioncited by 37
- 2024MR-Ben: A Meta-Reasoning Benchmark for Evaluating System-2 Thinking in LLMscited by 30
- 2024Living in the Moment: Can Large Language Models Grasp Co-Temporal Reasoning?cited by 25
- 2022Improving Temporal Generalization of Pre-trained Language Models with Lexical Semantic Changecited by 18
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Citing papers per year: 2025: 62; 2026: 36.
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- 2025Towards Reasoning Era: A Survey of Long Chain-of-Thought for Reasoning Large Language Modelscited by 381
- 2025From System 1 to System 2: A Survey of Reasoning Large Language Modelscited by 319
- 2025A Survey on Test-Time Scaling in Large Language Models: What, How, Where, and How Well?cited by 215
- 2025Skywork-Reward-V2: Scaling Preference Data Curation via Human-AI Synergycited by 204
- 2025Thinking with Images for Multimodal Reasoning: Foundations, Methods, and Future Frontierscited by 193
- 2025Can 1B LLM Surpass 405B LLM? Rethinking Compute-Optimal Test-Time Scalingcited by 135
- 2025VisualPRM: An Effective Process Reward Model for Multimodal Reasoningcited by 134
- 2025A Survey of Efficient Reasoning for Large Reasoning Models: Language, Multimodality, and Beyondcited by 131
- 2025GenPRM: Scaling Test-Time Compute of Process Reward Models via Generative Reasoningcited by 94
- 2025Evaluating Step-by-step Reasoning Traces: A Surveycited by 62
- 2025SpecReason: Fast and Accurate Inference-Time Compute via Speculative Reasoningcited by 60
- 2025Stop Summation: Min-Form Credit Assignment Is All Process Reward Model Needs for Reasoningcited by 49
12 most cited of 72 All 72 (JSON)
- 2026Interpreting Reasoning of Large Language Models via Partial Information Decomposition30 Sep 2026
- 2026Solving Every Step Is Not Enough: Milestone Oracles Reveal a Composition Gap in LLM Math Reasoning26 Sep 2026
- 2026Cliff: Learning Process Rewards from the First Mistake2 Sep 2026
- 2026SPEAR: Distilling Domain-Adaptive Reasoning Skeletons via Sequential Symbolic Alignment in Reinforcement Learning27 Aug 2026
- 2026Quality-Diversity Stress Tests for Process Reward Models:What Archive Coverage Can and Cannot Certify8 Aug 2026
- 2026Reference-Free Evaluation of Reasoning in Open-Ended Question Answering22 Jul 2026
- 2026The Hidden Bias of Process Reward Models:PRISM for Rewarding the Right Reasoning8 Jun 2026
- 2026A Primer in Post-Training Reasoning Data: What We Know About How It Works1 Jun 2026
- 2026Conformal Certification of Reasoning Trace Prefixes28 May 2026
- 2026OISD: On-Policy Internal Self-Distillation of Language Models27 May 2026
- 2026Scientific Logicality Enriched Methodology for LLM Reasoning: A Practice in Physics16 May 2026
- 2026Process Rewards with Learned Reliability15 May 2026
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- 2026LoopArena: Benchmarking Models as Runtime Controllers for Loop Engineering28 Aug 2026
- 2026Finding Where the Buck Stops: An Automated Failure Attribution-Based Reflection Framework for Multi-Agent Collaboration28 Aug 2026
- 2026QVal: Cheaply Evaluating Dense Supervision Signals for Long-Horizon LLM Agents30 Jun 2026
- 2026Where Do Deep-Research Agents Go Wrong? Span-Level Error Localization in Agent Trajectories1 Jun 2026
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- 2026PRPO: Aligning Process Reward with Outcome Reward in Policy Optimization12 Jan 2026
- 2025RoleRMBench & RoleRM: Towards Reward Modeling for Profile-Based Role Play in Dialogue Systems11 Dec 2025
- 2025AURA: Affordance-Understanding and Risk-aware Alignment Technique for Large Language Models8 Aug 2025
- 2025RewardBench 2: Advancing Reward Model Evaluation2 Jun 2025
- 2025Speculative Reward Model Boosts Decision Making Ability of LLMs Cost-Effectively31 May 2025
- 2025A Comprehensive Survey of Reward Models: Taxonomy, Applications, Challenges, and Future12 Apr 2025
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- 2026Certified Interface Aliases: Exact Collisions in Vision-Language Preprocessing, and When They Exist26 Sep 2026
- 2026Does CoT-Pass@k Really Check the CoT? A Multilingual Mathematical Audit26 Sep 2026
- 2026Locating Hidden Failures Makes Long-Horizon Agents More Reliable15 Sep 2026
- 2026Scalable Token-Level Hallucination Detection in Large Language Models12 May 2026
- 2026IF-RewardBench: Benchmarking Judge Models for Instruction-Following Evaluation5 Mar 2026
- 2025Evolution Strategies at Scale: LLM Fine-Tuning Beyond Reinforcement Learning29 Sep 2025
- 2025Shrinking the Generation-Verification Gap with Weak Verifiers22 Jun 2025
- 2025SMART: Self-Generating and Self-Validating Multi-Dimensional Assessment for LLMs' Mathematical Problem Solving22 May 2025
- 2025Evolutionary Guided Decoding: Iterative Value Refinement for LLMs4 Mar 2025
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