I study the mathematical foundations of learning and decision-making under uncertainty.
I am a Ph.D. student at Oregon State University, advised by
Huazheng Wang.
My research focuses on reinforcement learning theory, bandit algorithms, and statistical inference.
I am interested in how learning algorithms behave when models are imperfect, rewards are unreliable, or data are collected adaptively.
I received my B.S. in Statistics from the University of Science and Technology of China (USTC),
in the School of the Gifted Young. From July to October 2026, I was a research intern at
Microsoft Research Asia, working with Wei Chen on reward hacking and adaptive reward proxy refinement.
I am seeking Summer 2027 research internships in reinforcement learning, learning theory, and reliable agent evaluation.
Please get in touch if our research interests overlap.
Research
My work connects algorithm design with statistical analysis. Three questions guide my research.
How do modeling assumptions affect reinforcement learning?
I study KL regularization and function approximation, with a focus on what changes when the model class cannot fully represent the environment.
When does optimizing a reward lead to the wrong outcome?
I study reward poisoning and reward hacking, including how additional feedback can help identify and refine unreliable reward proxies.
How should a learner collect information?
I study bandit problems that balance decision quality, evaluation cost, and statistical inference, including improving proxies and network interference.
Online KL-Regularized Reinforcement Learning with Function Approximation under Misspecification
Haoyang Hong*, Zichen Wang*, Quanquan Gu, Huazheng Wang
RLC 2026
How does model misspecification affect online reinforcement learning with KL regularization and function approximation?
BibTeX
@inproceedings{hong2026onlinekl,
title={Online KL-Regularized Reinforcement Learning with Function Approximation under Misspecification},
author={Hong, Haoyang and Wang, Zichen and Gu, Quanquan and Wang, Huazheng},
booktitle={Reinforcement Learning Conference},
year={2026}
}
When Can You Poison Rewards? A Tight Characterization of Reward Poisoning in Linear MDPs
Jose Efraim Aguilar Escamilla*, Haoyang Hong*, Jiawei Li*, Haoyu Zhao, Xuezhou Zhang, Sanghyun Hong, Huazheng Wang
ICML 2026
When can an adversary change rewards to induce a target policy in a linear Markov decision process?
BibTeX
@inproceedings{aguilarescamilla2026poison,
title={When Can You Poison Rewards? A Tight Characterization of Reward Poisoning in Linear MDPs},
author={Aguilar Escamilla, Jose Efraim and Hong, Haoyang and Li, Jiawei and Zhao, Haoyu and Zhang, Xuezhou and Hong, Sanghyun and Wang, Huazheng},
booktitle={International Conference on Machine Learning},
year={2026}
}
Beyond Static Bias: Adaptive Multi-Fidelity Bandits with Improving Proxies
Muyun Lu*, Haoyang Hong*, Huazheng Wang, Ying Lin
arXiv:2605.08558 · 2026
How should a learner allocate evaluations across fidelity levels when cheaper proxy feedback improves with repeated use?
@inproceedings{wang2025design,
title={Design-Based Bandits under Network Interference: A Trade-off between Regret and Inference},
author={Wang, Zichen and Hong, Haoyang and Li, Chuanhao and Li, Haoxuan and Zhang, Zhiheng and Wang, Huazheng},
booktitle={Advances in Neural Information Processing Systems},
year={2025},
url={https://arxiv.org/abs/2510.07646}
}
Research Experience
Microsoft Research Asia (MSRA)
July–October 2026
Research Intern · Mentor: Wei Chen
My internship explored a practical question in reward hacking.
How can occasional, costly feedback improve a cheap reward proxy, and when should the system request further evaluation?
Investigated extensions of existing reward hacking theory to understand how optimizing a proxy reward affects the true reward and how additional feedback can guide proxy refinement.
Studied adaptive methods for refining reward proxies using feedback from more capable LLMs, human supervision, or comprehensive environment evaluations.
The aim was to reduce reliance on costly feedback as training progresses, while flagging potential proxy failures for further evaluation.
Conducted preliminary experiments with coding agents and robotics tasks to examine proxy refinement, discrepancies between proxy and true rewards, and evaluation cost.
Education
Oregon State University
September 2024–present
Ph.D. in Artificial Intelligence · Expected September 2029