Intra-Trajectory Consistency for Reward Modeling
- URL: http://arxiv.org/abs/2506.09096v3
- Date: Mon, 16 Jun 2025 04:03:11 GMT
- Title: Intra-Trajectory Consistency for Reward Modeling
- Authors: Chaoyang Zhou, Shunyu Liu, Zengmao Wang, Di Wang, Rong-Cheng Tu, Bo Du, Dacheng Tao,
- Abstract summary: 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.
- Score: 67.84522106537274
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Reward models are critical for improving large language models (LLMs), particularly in reinforcement learning from human feedback (RLHF) or inference-time verification. Current reward modeling typically relies on scores of overall responses to learn the outcome rewards for the responses. However, since the response-level scores are coarse-grained supervision signals, the reward model struggles to identify the specific components within a response trajectory that truly correlate with the scores, leading to poor generalization on unseen responses. In this paper, we propose to leverage generation probabilities to establish reward consistency between processes in the response trajectory, which allows the response-level supervisory signal to propagate across processes, thereby providing additional fine-grained signals for reward learning. Building on analysis under the Bayesian framework, we develop an intra-trajectory consistency regularization to enforce that adjacent processes with higher next-token generation probability maintain more consistent rewards. We apply the proposed regularization to the advanced outcome reward model, improving its performance on RewardBench. Besides, 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. Our code is provided in https://github.com/chaoyang101/ICRM.
Related papers
- Dynamic and Generalizable Process Reward Modeling [74.36829922727026]
We propose Dynamic and Generalizable Process Reward Modeling (DG-PRM), which features a reward tree to capture and store fine-grained, multi-dimensional reward criteria.<n> Experimental results show that DG-PRM achieves stunning performance on prevailing benchmarks, significantly boosting model performance across tasks with dense rewards.
arXiv Detail & Related papers (2025-07-23T18:17:22Z) - Reward Models Can Improve Themselves: Reward-Guided Adversarial Failure Mode Discovery for Robust Reward Modeling [27.11560841914813]
We introduce REFORM, a self-improving reward modeling framework that enhances robustness by using the reward model itself to guide the generation of falsely scored responses.<n>We evaluate REFORM on two widely used preference datasets Anthropic Helpful Harmless (HH) and PKU Beavertails.
arXiv Detail & Related papers (2025-07-08T21:56:33Z) - RAG-Zeval: Towards Robust and Interpretable Evaluation on RAG Responses through End-to-End Rule-Guided Reasoning [64.46921169261852]
RAG-Zeval is a novel end-to-end framework that formulates faithfulness and correctness evaluation as a rule-guided reasoning task.<n>Our approach trains evaluators with reinforcement learning, facilitating compact models to generate comprehensive and sound assessments.<n>Experiments demonstrate RAG-Zeval's superior performance, achieving the strongest correlation with human judgments.
arXiv Detail & Related papers (2025-05-28T14:55:33Z) - Reward Reasoning Model [104.39256985858428]
Reward Reasoning Models (RRMs) are designed to execute a deliberate reasoning process before generating final rewards.<n>We implement a reinforcement learning framework that fosters self-evolved reward reasoning capabilities.<n> Notably, RRMs can adaptively exploit test-time compute to further improve reward accuracy.
arXiv Detail & Related papers (2025-05-20T17:58:03Z) - Agentic Reward Modeling: Integrating Human Preferences with Verifiable Correctness Signals for Reliable Reward Systems [54.4392552373835]
Reward models (RMs) are crucial for the training and inference-time scaling up of large language models (LLMs)<n>We propose agentic reward modeling, a reward system that combines reward models with verifiable correctness signals to provide reliable rewards.<n>We conduct comprehensive experiments on existing reward model benchmarks and inference time best-of-n searches on real-world downstream tasks.
arXiv Detail & Related papers (2025-02-26T17:19:12Z) - Beyond Simple Sum of Delayed Rewards: Non-Markovian Reward Modeling for Reinforcement Learning [44.770495418026734]
Reinforcement Learning (RL) empowers agents to acquire various skills by learning from reward signals.
Traditional methods assume the existence of underlying Markovian rewards and that the observed delayed reward is simply the sum of instance-level rewards.
We propose Composite Delayed Reward Transformer (CoDeTr), which incorporates a specialized in-sequence attention mechanism.
arXiv Detail & Related papers (2024-10-26T13:12:27Z) - Evaluating Robustness of Reward Models for Mathematical Reasoning [14.97819343313859]
We introduce a new design for reliable evaluation of reward models, and to validate this, we construct RewardMATH.
We demonstrate that the scores on RewardMATH strongly correlate with the results of optimized policy and effectively estimate reward overoptimization.
arXiv Detail & Related papers (2024-10-02T16:39:58Z) - RewardBench: Evaluating Reward Models for Language Modeling [100.28366840977966]
We present RewardBench, a benchmark dataset and code-base for evaluation of reward models.
The dataset is a collection of prompt-chosen-rejected trios spanning chat, reasoning, and safety.
On the RewardBench leaderboard, we evaluate reward models trained with a variety of methods.
arXiv Detail & Related papers (2024-03-20T17:49:54Z) - Dense Reward for Free in Reinforcement Learning from Human Feedback [64.92448888346125]
We leverage the fact that the reward model contains more information than just its scalar output.
We use these attention weights to redistribute the reward along the whole completion.
Empirically, we show that it stabilises training, accelerates the rate of learning, and, in practical cases, may lead to better local optima.
arXiv Detail & Related papers (2024-02-01T17:10:35Z) - Interpretable Reward Redistribution in Reinforcement Learning: A Causal
Approach [45.83200636718999]
A major challenge in reinforcement learning is to determine which state-action pairs are responsible for future rewards that are delayed.
We propose to explicitly model the contributions of state and action from a causal perspective, resulting in an interpretable reward redistribution.
Experimental results show that our method outperforms state-of-the-art methods.
arXiv Detail & Related papers (2023-05-28T21:51:38Z) - Distributional Reward Estimation for Effective Multi-Agent Deep
Reinforcement Learning [19.788336796981685]
We propose a novel Distributional Reward Estimation framework for effective Multi-Agent Reinforcement Learning (DRE-MARL)
Our main idea is to design the multi-action-branch reward estimation and policy-weighted reward aggregation for stabilized training.
The superiority of the DRE-MARL is demonstrated using benchmark multi-agent scenarios, compared with the SOTA baselines in terms of both effectiveness and robustness.
arXiv Detail & Related papers (2022-10-14T08:31:45Z)
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.