Yilei Chen

Hello, I am a 4th-year PhD student at Boston University majoring in Systems Engneering with Operations Research concentration. Previously, I got my bachelor’s degree in Physics at University of Science and Technology of China (USTC).

I am fortunately working with Prof. Aldo Pacchiano and Prof. Yannis Paschalidis on Reinforcement Learning and Large Language Models. My research focuses on LLM reasoning, RL Post-training and AI Agents with the goal of enabling efficient, high-quality, and diverse reasoning in Large Language Models.

Publications

When Less is Enough: Efficient Inference via Collaborative Reasoning
Yilei Chen, Sharut Gupta, Yannis Paschalidis, Ayush Sekhari, Aldo Pacchiano
arXiv pre-print

Post-training Large Language Models for Diverse High-Quality Responses
Yilei Chen, Souradip Chakraborty, Lorenz Wolf, Ioannis Ch. Paschalidis, Aldo Pacchiano
International Conference on Learning Representations (ICLR), 2026

Scaling In-Context Online Learning Capability of LLMs via Cross-Episode Meta-RL
Xiaofeng Lin, Sirou Zhu, Yilei Chen, Mingyu Chen, Hejian Sang, Ioannis Paschalidis
Zhipeng Wang, Aldo Pacchiano, Xuezhou Zhang
arXiv pre-print

Multiple-policy Evaluation via Density Estimation
Yilei Chen, Aldo Pacchiano, Ioannis Ch. Paschalidis
International Conference on Machine Learning (ICML), 2025

Provably Efficient Off-Policy Adversarial Imitation Learning with Convergence Guarantees
Yilei Chen, Vittorio Giammarino, James Queeney, Ioannis Ch. Paschalidis
Transactions on Machine Learning Research (TMLR), 2026

Services

Conference reviewer: ICLR, NeurIPS (Top reviewer, 2025), ICML (Gold reviewer, 2026), AISTATS

Miscellaneous

I am an amateur soccer player. I am also interested in hiking, poker and Soulslike games.