Beyond Outcome Verification: Verifiable Process Reward Models for Structured Reasoning
- URL: http://arxiv.org/abs/2601.17223v1
- Date: Fri, 23 Jan 2026 23:22:20 GMT
- Title: Beyond Outcome Verification: Verifiable Process Reward Models for Structured Reasoning
- Authors: Massimiliano Pronesti, Anya Belz, Yufang Hou,
- Abstract summary: Verifiable Process Reward Models (VPRMs) are a reinforcement-learning framework in which intermediate reasoning steps are checked by deterministic, rule-based verifiers.<n>We apply VPRMs to risk-of-bias assessment for medical evidence synthesis.<n>Results show that VPRMs achieve up to 20% higher F1 than state-of-the-art models and 6.5% higher than verifiable outcome rewards.
- Score: 14.632557283678898
- License: http://creativecommons.org/licenses/by-nc-nd/4.0/
- Abstract: Recent work on reinforcement learning with verifiable rewards (RLVR) has shown that large language models (LLMs) can be substantially improved using outcome-level verification signals, such as unit tests for code or exact-match checks for mathematics. In parallel, process supervision has long been explored as a way to shape the intermediate reasoning behaviour of LLMs, but existing approaches rely on neural judges to score chain-of-thought steps, leaving them vulnerable to opacity, bias, and reward hacking. To address this gap, we introduce Verifiable Process Reward Models (VPRMs), a reinforcement-learning framework in which intermediate reasoning steps are checked by deterministic, rule-based verifiers. We apply VPRMs to risk-of-bias assessment for medical evidence synthesis, a domain where guideline-defined criteria and rule-based decision paths enable programmatic verification of reasoning traces. Across multiple datasets, we find that VPRMs generate reasoning that adheres closely to domain rules and achieve substantially higher coherence between step-level decisions and final labels. Results show that VPRMs achieve up to 20% higher F1 than state-of-the-art models and 6.5% higher than verifiable outcome rewards, with substantial gains in evidence grounding and logical coherence.
Related papers
- EvalQReason: A Framework for Step-Level Reasoning Evaluation in Large Language Models [0.8399688944263844]
We present EvalQReason, a framework that quantifies LLM reasoning quality through step-level probability distribution analysis.<n>The framework introduces two complementary algorithms: Consecutive Step Divergence (CSD), which measures local coherence between adjacent reasoning steps, and Step-to-Final Convergence (SFC), which assesses global alignment with final answers.
arXiv Detail & Related papers (2026-02-02T16:32:40Z) - ProRAG: Process-Supervised Reinforcement Learning for Retrieval-Augmented Generation [54.071574153853994]
ProRAG is a process-supervised reinforcement learning framework designed to integrate learned step-level supervision into the online optimization loop.<n>Our framework consists of four stages: (1) Supervised Policy Warmup to initialize the model with a structured reasoning format; (2) construction of an MCTS-based Process Reward Model (PRM) to quantify intermediate reasoning quality; (3) PRM-Guided Reasoning Refinement to align the policy with fine-grained process preferences; and (4) Process-Supervised Reinforcement Learning with a dual-granularity advantage mechanism.
arXiv Detail & Related papers (2026-01-29T16:04:59Z) - From <Answer> to <Think>: Multidimensional Supervision of Reasoning Process for LLM Optimization [62.07990937720985]
Dimension-level Reward Model (DRM) is a new supervision framework for Large Language Models.<n>DRM evaluates the quality of a reasoning process along three fundamental, complementary, and interpretable dimensions.<n> Experimental results show that DRM provides effective supervision signals, guides the optimization of LLMs and enhances their reasoning ability.
arXiv Detail & Related papers (2025-10-13T14:29:15Z) - A Survey of Process Reward Models: From Outcome Signals to Process Supervisions for Large Language Models [31.650962391182798]
This survey provides a systematic overview of PRMs through the full loop.<n>We summarize applications across math, code, text, multimodal reasoning, robotics, and agents.<n>Our goal is to clarify design spaces, reveal open challenges, and guide future research toward fine-grained, robust reasoning alignment.
arXiv Detail & Related papers (2025-10-09T10:35:31Z) - Linking Process to Outcome: Conditional Reward Modeling for LLM Reasoning [30.302863491794543]
Process Reward Models (PRMs) aim to guide their step-by-step reasoning toward a final answer.<n>Existing PRMs fail to capture inter-step dependencies, or struggle to align process rewards with the final outcome.<n>We propose Conditional Reward Modeling that frames reasoning as a temporal process leading to a correct answer.
arXiv Detail & Related papers (2025-09-30T17:38:45Z) - Conditional Advantage Estimation for Reinforcement Learning in Large Reasoning Models [50.84995206660551]
We introduce Conditional advANtage estimatiON (CANON) to amplify the impact of a target metric without presuming its direction.<n>CANON based on entropy consistently outperforms prior methods on both math reasoning and high-complexity logic tasks.
arXiv Detail & Related papers (2025-09-28T16:33:07Z) - ReasonFlux-PRM: Trajectory-Aware PRMs for Long Chain-of-Thought Reasoning in LLMs [75.72672339168092]
We introduce ReasonFlux-PRM, a novel trajectory-aware PRM to evaluate trajectory-response type of reasoning traces.<n>ReasonFlux-PRM incorporates both step-level and trajectory-level supervision, enabling fine-grained reward assignment aligned with structured chain-of-thought data.<n>Our derived ReasonFlux-PRM-7B yields consistent performance improvements, achieving average gains of 12.1% in supervised fine-tuning, 4.5% in reinforcement learning, and 6.3% in test-time scaling.
arXiv Detail & Related papers (2025-06-23T17:59:02Z) - Intra-Trajectory Consistency for Reward Modeling [67.84522106537274]
We develop an intra-trajectory consistency regularization to enforce that adjacent processes with higher next-token generation probability maintain more consistent rewards.<n>We show that the reward model trained with the proposed regularization induces better DPO-aligned policies and achieves better best-of-N (BON) inference-time verification results.
arXiv Detail & Related papers (2025-06-10T12:59:14Z) - ReARTeR: Retrieval-Augmented Reasoning with Trustworthy Process Rewarding [25.329712997545794]
We propose Retrieval-Augmented Reasoning through Trustworthy Process Rewarding (ReARTeR)<n>ReARTeR enhances RAG systems' reasoning capabilities through post-training and test-time scaling.<n> Experimental results on multi-step reasoning benchmarks demonstrate significant improvements.
arXiv Detail & Related papers (2025-01-14T05:56:26Z) - The Lessons of Developing Process Reward Models in Mathematical Reasoning [62.165534879284735]
Process Reward Models (PRMs) aim to identify and mitigate intermediate errors in the reasoning processes.<n>We develop a consensus filtering mechanism that effectively integrates Monte Carlo (MC) estimation with Large Language Models (LLMs)<n>We release a new state-of-the-art PRM that outperforms existing open-source alternatives.
arXiv Detail & Related papers (2025-01-13T13:10:16Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.