English
Related papers

Related papers: How Neural Reward Models Learn Features for Policy…

200 papers

We study the problem of learning a single neuron with respect to the $L_2^2$-loss in the presence of adversarial distribution shifts, where the labels can be arbitrary, and the goal is to find a ``best-fit'' function. More precisely, given…

Machine Learning · Computer Science 2024-11-12 Shuyao Li , Sushrut Karmalkar , Ilias Diakonikolas , Jelena Diakonikolas

Learning effective policies for sparse objectives is a key challenge in Deep Reinforcement Learning (RL). A common approach is to design task-related dense rewards to improve task learnability. While such rewards are easily interpreted,…

Machine Learning · Computer Science 2020-10-12 Hassam Sheikh , Shauharda Khadka , Santiago Miret , Somdeb Majumdar

Reinforcement Learning has suffered from poor reward specification, and issues for reward hacking even in simple enough domains. Preference Based Reinforcement Learning attempts to solve the issue by utilizing binary feedbacks on queried…

Artificial Intelligence · Computer Science 2023-02-20 Mudit Verma , Subbarao Kambhampati

Consider an auto-regressive model that produces outputs x (e.g., answers to questions, molecules) each of which can be summarized by an attribute vector y (e.g., helpfulness vs. harmlessness, or bio-availability vs. lipophilicity). An…

Machine Learning · Computer Science 2026-04-20 Alexander Peysakhovich , William Berman

Reward shaping is a technique in reinforcement learning that addresses the sparse-reward problem by providing more frequent and informative rewards. We introduce a self-adaptive and highly efficient reward shaping mechanism that…

Machine Learning · Computer Science 2025-03-03 Haozhe Ma , Zhengding Luo , Thanh Vinh Vo , Kuankuan Sima , Tze-Yun Leong

Inverse reinforcement learning is the problem of inferring a reward function from an optimal policy or demonstrations by an expert. In this work, it is assumed that the reward is expressed as a reward machine whose transitions depend on…

Machine Learning · Computer Science 2025-10-23 Mohamad Louai Shehab , Antoine Aspeel , Necmiye Ozay

Model-based reinforcement learning methods typically learn models for high-dimensional state spaces by aiming to reconstruct and predict the original observations. However, drawing inspiration from model-free reinforcement learning, we…

Machine Learning · Computer Science 2019-12-10 Aaron Havens , Yi Ouyang , Prabhat Nagarajan , Yasuhiro Fujita

This work proposes `PET', a novel pessimistic reward fine-tuning method, to learn a pessimistic reward model robust against reward hacking in offline reinforcement learning from human feedback (RLHF). Traditional reward modeling techniques…

Machine Learning · Computer Science 2025-05-28 Yinglun Xu , Hangoo Kang , Tarun Suresh , Yuxuan Wan , Gagandeep Singh

The ability of reinforcement learning algorithms to learn effective policies is determined by the rewards available during training. However, for practical problems, obtaining large quantities of reward labels is often infeasible due to…

Machine Learning · Computer Science 2025-10-02 Shreyas Chaudhari , Renhao Zhang , Philip S. Thomas , Bruno Castro da Silva

We study contextual bandits with finitely many actions in which the reward of each arm follows a single-index model with an arm-specific index parameter and an unknown nonparametric link function. We consider a regime in which arms…

Machine Learning · Statistics 2026-03-20 Sakshi Arya , Satarupa Bhattacharjee , Bharath K. Sriperumbudur

Despite the increasing popularity of policy gradient methods, they are yet to be widely utilized in sample-scarce applications, such as robotics. The sample efficiency could be improved by making best usage of available information. As a…

Machine Learning · Computer Science 2023-11-03 Qingfeng Lan , Samuele Tosatto , Homayoon Farrahi , A. Rupam Mahmood

The problem of reinforcement learning is considered where the environment or the model undergoes a change. An algorithm is proposed that an agent can apply in such a problem to achieve the optimal long-time discounted reward. The algorithm…

Systems and Control · Electrical Eng. & Systems 2023-04-25 Wuxia Chen , Taposh Banerjee , Jemin George , Carl Busart

Numerous algorithms have been proposed to $\textit{align}$ language models to remove undesirable behaviors. However, the challenges associated with a very large state space and creating a proper reward function often result in various…

Computation and Language · Computer Science 2024-06-06 Suraj Anand , David Getzen

Reward learning typically relies on a single feedback type or combines multiple feedback types using manually weighted loss terms. Currently, it remains unclear how to jointly learn reward functions from heterogeneous feedback types such as…

Machine Learning · Computer Science 2026-02-18 Raphaël Baur , Yannick Metz , Maria Gkoulta , Mennatallah El-Assady , Giorgia Ramponi , Thomas Kleine Buening

In this paper, we study the problem of deceptive reinforcement learning to preserve the privacy of a reward function. Reinforcement learning is the problem of finding a behaviour policy based on rewards received from exploratory behaviour.…

Machine Learning · Computer Science 2021-02-08 Zhengshang Liu , Yue Yang , Tim Miller , Peta Masters

Imitation learning is an effective alternative approach to learn a policy when the reward function is sparse. In this paper, we consider a challenging setting where an agent and an expert use different actions from each other. We assume…

Machine Learning · Computer Science 2019-08-27 Konrad Zolna , Negar Rostamzadeh , Yoshua Bengio , Sungjin Ahn , Pedro O. Pinheiro

Reinforcement learning from human feedback usually models preferences using a reward function that does not distinguish between people. We argue that this is unlikely to be a good design choice in contexts with high potential for…

In Reinforcement Learning (abbreviated as RL), an agent interacts with the environment via a set of possible actions, and a reward is generated from some unknown distribution. The task here is to find an optimal set of actions such that the…

Machine Learning · Computer Science 2025-07-21 Aditi Anand , Suman Banerjee , Dildar Ali

The aim of this paper is to study the reward based policy exploration problem in a supervised learning approach and enable robots to form complex movement trajectories in challenging reward settings and search spaces. For this, the…

Robotics · Computer Science 2020-11-10 M. Tuluhan Akbulut , Utku Bozdogan , Ahmet Tekden , Emre Ugur

State-of-the-art model-based reinforcement learning methods train policies on imagined rollouts. These rollouts are trajectories generated by a learned dynamics model and are scored by a learned reward model, but without querying the true…

Machine Learning · Computer Science 2026-05-13 Nadav Timor , Ravid Shwartz-Ziv , Micah Goldblum , Yann LeCun , David Harel