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Related papers: UCPO: Uncertainty-Aware Policy Optimization

200 papers

Despite their sophisticated general-purpose capabilities, Large Language Models (LLMs) often fail to align with diverse individual preferences because standard post-training methods, like Reinforcement Learning with Human Feedback (RLHF),…

Large language model (LLM) alignment via reinforcement learning from human preferences (RLHF) suffers from unstable policy updates, ambiguous gradient directions, poor interpretability, and high gradient variance in mainstream pairwise…

Machine Learning · Computer Science 2026-05-12 Hao Yu

Group Relative Policy Optimization (GRPO) has significantly advanced the reasoning ability of large language models (LLMs), particularly by boosting their mathematical performance. However, GRPO and related entropy-regularization methods…

Computation and Language · Computer Science 2025-10-13 Xingyu Lin , Yilin Wen , En Wang , Du Su , Wenbin Liu , Chenfu Bao , Zhonghou Lv

Reinforcement learning with verifiers (RLVR) has become a central paradigm for improving LLM reasoning, yet popular group-based optimization algorithms like GRPO often suffer from exploration collapse, where the models prematurely converge…

Artificial Intelligence · Computer Science 2026-05-19 Haoxuan Chen , Tianming Liang , Wei-Shi Zheng , Jian-Fang Hu

This work studies the problem of large language model (LLM) unlearning, aiming to remove unwanted data influences (e.g., copyrighted or harmful content) while preserving model utility. Despite the increasing demand for unlearning, a…

Computation and Language · Computer Science 2025-10-21 Chongyu Fan , Jiancheng Liu , Licong Lin , Jinghan Jia , Ruiqi Zhang , Song Mei , Sijia Liu

Process reward models (PRMs) allow for fine-grained credit assignment in reinforcement learning (RL), and seemingly contrast with outcome reward models (ORMs), which assign a single reward to an entire trajectory. However, we provide…

Machine Learning · Computer Science 2026-05-29 Michael Sullivan , Alexander Koller

Group Relative Policy Optimization (GRPO) has emerged as a promising approach for improving the reasoning capabilities of large language models. However, it struggles to effectively balance the tradeoff between exploration and exploitation…

Computation and Language · Computer Science 2026-05-13 Cheng Wang , Qin Liu , Wenxuan Zhou , Muhao Chen

Tables contain rich structured information, yet when stored as images their contents remain "locked" within pixels. Converting table images into LaTeX code enables faithful digitization and reuse, but current multimodal large language…

Artificial Intelligence · Computer Science 2026-04-14 Yunfan Yang , Cuiling Lan , Jitao Sang , Yan Lu

Reinforcement learning algorithms are fundamental to align large language models with human preferences and to enhance their reasoning capabilities. However, current reinforcement learning algorithms often suffer from training instability…

Machine Learning · Computer Science 2025-06-05 Yaru Hao , Li Dong , Xun Wu , Shaohan Huang , Zewen Chi , Furu Wei

Recently, Large Language Models (LLMs) have rapidly evolved, approaching Artificial General Intelligence (AGI) while benefiting from large-scale reinforcement learning to enhance Human Alignment (HA) and Reasoning. Recent reward-based…

Machine Learning · Computer Science 2025-06-19 Xuerui Su , Shufang Xie , Guoqing Liu , Yingce Xia , Renqian Luo , Peiran Jin , Zhiming Ma , Yue Wang , Zun Wang , Yuting Liu

While large language models (LLMs) have recently made tremendous progress towards solving challenging AI problems, they have done so at increasingly steep computational and API costs. We propose a novel strategy where we combine multiple…

Machine Learning · Computer Science 2026-03-24 Wenwen Si , Sooyong Jang , Insup Lee , Osbert Bastani

Prompt optimization algorithms for Large Language Models (LLMs) excel in multi-step reasoning but still lack effective uncertainty estimation. This paper introduces a benchmark dataset to evaluate uncertainty metrics, focusing on Answer,…

Machine Learning · Computer Science 2024-12-30 Pei-Fu Guo , Yun-Da Tsai , Shou-De Lin

Post-training paradigms for Large Language Models (LLMs), primarily Supervised Fine-Tuning (SFT) and Reinforcement Learning (RL), face a fundamental dilemma: SFT provides stability (low variance) but suffers from high fitting bias, while RL…

Machine Learning · Computer Science 2026-04-13 Taojie Zhu , Dongyang Xu , Ding Zou , Sen Zhao , Qiaobo Hao , Zhiguo Yang , Yonghong He

Prediction deviations of different uncertainties have varying impacts on downstream decision-making. Improving the prediction accuracy of critical uncertainties with significant impacts on decision-making quality yields better optimization…

Systems and Control · Electrical Eng. & Systems 2025-10-17 Yingrui Zhuang , Lin Cheng , Can Wan , Rui Xie , Ning Qi , Yue Chen

Post-training has become central to improving reasoning and alignment in large language models, where critic-free models enable scalable learning from model-generated outputs but lack principled mechanisms to distinguish informative from…

Machine Learning · Computer Science 2026-05-22 Zheyuan Zhang , Kaiwen Shi , Han Bao , Zehong Wang , Tianyi Ma , Yanfang Ye

Safety and trustworthiness are indispensable requirements for real-world applications of AI systems using large language models (LLMs). This paper formulates human value alignment as an optimization problem of the language model policy to…

Machine Learning · Computer Science 2024-10-22 Akifumi Wachi , Thien Q. Tran , Rei Sato , Takumi Tanabe , Youhei Akimoto

Counterfactual learning to rank (CLTR) can be risky and, in various circumstances, can produce sub-optimal models that hurt performance when deployed. Safe CLTR was introduced to mitigate these risks when using inverse propensity scoring to…

Machine Learning · Computer Science 2024-08-08 Shashank Gupta , Harrie Oosterhuis , Maarten de Rijke

Reinforcement learning from human feedback (RLHF) has demonstrated great promise in aligning large language models (LLMs) with human preference. Depending on the availability of preference data, both online and offline RLHF are active areas…

Machine Learning · Computer Science 2025-02-20 Shicong Cen , Jincheng Mei , Katayoon Goshvadi , Hanjun Dai , Tong Yang , Sherry Yang , Dale Schuurmans , Yuejie Chi , Bo Dai

Chain-of-thought explanations are widely used to inspect the decision process of large language models (LLMs) and to evaluate the trustworthiness of model outputs, making them important for effective collaboration between LLMs and humans.…

Computation and Language · Computer Science 2025-07-16 Pedro Ferreira , Wilker Aziz , Ivan Titov

Reinforcement learning algorithms such as GRPO have driven recent advances in large language model (LLM) reasoning. While scaling the number of rollouts stabilizes training, existing approaches suffer from limited exploration on challenging…

Machine Learning · Computer Science 2026-05-26 Udbhav Bamba , Minghao Fang , Yifan Yu , Haizhong Zheng , Fan Lai