activity
20232026
collaborators

6 papers

cs.LG2026

Efficient Preference Poisoning Attack on Offline RLHF

Chenye Yang, Weiyu Xu, Lifeng Lai

Offline Reinforcement Learning from Human Feedback (RLHF) pipelines such as Direct Preference Optimization (DPO) train on a pre-collected preference dataset, which makes them vulne…

cs.LG2025

Learn to Change the World: Multi-level Reinforcement Learning with Model-Changing Actions

Ziqing Lu, Babak Hassibi, Lifeng Lai +1

Reinforcement learning usually assumes a given or sometimes even fixed environment in which an agent seeks an optimal policy to maximize its long-term discounted reward. In contras…

cs.LG2025

Provably Invincible Adversarial Attacks on Reinforcement Learning Systems: A Rate-Distortion Information-Theoretic Approach

Ziqing Lu, Lifeng Lai, Weiyu Xu

Reinforcement learning (RL) for the Markov Decision Process (MDP) has emerged in many security-related applications, such as autonomous driving, financial decisions, and drone/robo…

cs.MA2024

Camouflage Adversarial Attacks on Multiple Agent Systems

Ziqing Lu, Guanlin Liu, Lifeng Lai +1

The multi-agent reinforcement learning systems (MARL) based on the Markov decision process (MDP) have emerged in many critical applications. To improve the robustness/defense of MA…

cs.LG2023

Optimal Cost Constrained Adversarial Attacks For Multiple Agent Systems

Ziqing Lu, Guanlin Liu, Lifeng Lai +1

Finding optimal adversarial attack strategies is an important topic in reinforcement learning and the Markov decision process. Previous studies usually assume one all-knowing coord…

cs.LG2023

Distributed Dual Coordinate Ascent with Imbalanced Data on a General Tree Network

Myung Cho, Lifeng Lai, Weiyu Xu

In this paper, we investigate the impact of imbalanced data on the convergence of distributed dual coordinate ascent in a tree network for solving an empirical loss minimization pr…