RVPO: Risk-Sensitive Alignment via Variance Regularization
On the map: LLM alignment / RLHF / preference optimisation → LLM preference optimization methods
Abstract (arXiv)
Current critic-less RLHF methods aggregate multi-objective rewards via an arithmetic mean, leaving them vulnerable to constraint neglect: high-magnitude success in one objective can numerically offset critical failures in others (e.g., safety or formatting), masking low-performing "bottleneck" rewards vital for reliable multi-objective alignment. We propose Reward-Variance Policy Optimization (RVPO), a risk-sensitive framework that penalizes inter-reward variance during advantage aggregation, shifting the objective from "maximize sum" to "maximize consistency." We show via Taylor expansion that a LogSumExp (SoftMin) operator effectively acts as a smooth variance penalty. We evaluate RVPO on rubric-based medical and scientific reasoning with up to 17 concurrent LLM-judged reward signals (Qwen2.5-3B/7B/14B) and on tool-calling with rule-based constraints (Qwen2.5-1.5B/3B). By preventing the model from neglecting difficult constraints to exploit easier objectives, RVPO improves overall scores on HealthBench (0.261 vs. 0.215 for GDPO at 14B, p < 0.001) and maintains competitive accuracy on GPQA-Diamond without the late-stage degradation observed in other multi-reward methods, demonstrating that variance regularization mitigates constraint neglect across model scales without sacrificing general capabilities.
Key facts. Cited by 3 papers in the map (data through 14 Oct 2026). Placed in LLM preference optimization methods, one of 10 directions in LLM alignment / RLHF / preference optimisation. Builds on 33 of its 39 references that are in the map. First posted on arXiv 7 May 2026.
Builds on
33 of 39 references.
Closest ancestors · 7
Same direction, newest first
- 2026Reward-free Alignment for Conflicting Objectives2 Feb
- 2025Beyond RLHF and NLHF: Population-Proportional Alignment under an Axiomatic Framework5 Jun
- 2025Multi-objective Large Language Model Alignment with Hierarchical Experts27 May
- 2025PARM: Multi-Objective Test-Time Alignment via Preference-Aware Autoregressive Reward Model6 May
- 2024SimPO: Simple Preference Optimization with a Reference-Free Reward23 May
- 2024Disentangling Length from Quality in Direct Preference Optimization28 Mar
- 2022Training language models to follow instructions with human feedback4 Mar
Other references · 26
- 2024DeepSeekMath: Pushing the Limits of Mathematical Reasoning in Open Language Modelscited by 9,379
- 2023Direct Preference Optimization: Your Language Model is Secretly a Reward Modelcited by 8,065
- 2024Qwen2.5 Technical Reportcited by 4,942
- 2023GPQA: A Graduate-Level Google-Proof Q&A Benchmarkcited by 2,879
- 2025DAPO: An Open-Source LLM Reinforcement Learning System at Scalecited by 2,810
- 2024HybridFlow: A Flexible and Efficient RLHF Frameworkcited by 2,057
- 2022Scaling Laws for Reward Model Overoptimizationcited by 1,095
- 2017Constrained Policy Optimizationcited by 983
- 2023Safe RLHF: Safe Reinforcement Learning from Human Feedbackcited by 656
- 2025HealthBench: Evaluating Large Language Models Towards Improved Human Healthcited by 429
- 2025Rubrics as Rewards: Reinforcement Learning Beyond Verifiable Domainscited by 366
- 2025ToolRL: Reward is All Tool Learning Needscited by 362
14 more
- 2021A Practical Guide to Multi-Objective Reinforcement Learning and Planningcited by 256
- 2023Rewarded soups: towards Pareto-optimal alignment by interpolating weights fine-tuned on diverse rewardscited by 243
- 2024HelpSteer2: Open-source dataset for training top-performing reward modelscited by 236
- 2026GDPO: Group reward-Decoupled Normalization Policy Optimization for Multi-reward RL Optimizationcited by 193
- 2019Constrained Reinforcement Learning Has Zero Duality Gapcited by 151
- 2024ODIN: Disentangled Reward Mitigates Hacking in RLHFcited by 136
- 2025Checklists Are Better Than Reward Models For Aligning Language Modelscited by 128
- 2024Rule Based Rewards for Language Model Safetycited by 108
- 2024LLM-Rubric: A Multidimensional, Calibrated Approach to Automated Evaluation of Natural Language Textscited by 87
- 2025Multi-Attribute Steering of Language Models via Targeted Interventioncited by 46
- 2025Optimizing Safe and Aligned Language Generation: A Multi-Objective GRPO Approachcited by 24
- 2024The Accuracy Paradox in RLHF: When Better Reward Models Don't Yield Better Language Modelscited by 19
- 2025Mitigating Reward Over-Optimization in RLHF via Behavior-Supported Regularizationcited by 14
- 2020Risk-Sensitive Deep RL: Variance-Constrained Actor-Critic Provably Finds Globally Optimal Policycited by 7
Built on by
Citing papers per year: 2026: 3.
3 papers.
- 2026PReMISE: Policy Rubrics as Measurement Specifications for LLM Judgescited by 4
- 2026Advantage Scale Calibration Imbalance in Group-Relative Optimization under Low-Variance Rewards: Diagnosis and Bounded Recoverycited by 1
- 2026Make Sparse Rewards Count: Density-Aware Reward Aggregation for Multi-Reward RLcited by 0
- 2026Make Sparse Rewards Count: Density-Aware Reward Aggregation for Multi-Reward RL30 Sep 2026
- 2026Advantage Scale Calibration Imbalance in Group-Relative Optimization under Low-Variance Rewards: Diagnosis and Bounded Recovery27 Aug 2026
- 2026PReMISE: Policy Rubrics as Measurement Specifications for LLM Judges29 May 2026
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- 2026f-GRPO and Beyond: Divergence-Based Reinforcement Learning Algorithms for General LLM Alignment
- 2026Reward Shaping for (Inference-Time) Alignment: A Stackelberg Game Perspective
- 2026When Right Meets Wrong: Bilateral Context Conditioning with Reward-Confidence Correction for GRPO
- 2026ORPG: Reconciling Multiple Reward Objectives through Objective-wise Policy Gradients
- 2026DVAO: Dynamic Variance-adaptive Advantage Optimization for Multi-reward Reinforcement Learning
- 2026GVPO++: Group Variance Policy Optimization for LLM Post-Training and On-Policy Distillation
- 2025Preference Robustness for DPO with Applications to Public Health