3 papers
stat.ML2026
When Does Trajectory-Level Supervision Permit Efficient Offline Reinforcement Learning?
Xuanfei Ren, Tengyang Xie
Offline reinforcement learning is typically analyzed under process-level reward supervision, yet many sequential decision datasets record only trajectory-level outcomes. We develop…
cs.LG2026
POLCA: Stochastic Generative Optimization with LLM
Xuanfei Ren, Allen Nie, Tengyang Xie +1
Optimizing complex systems, ranging from LLM prompts to multi-turn agents, traditionally requires labor-intensive manual iteration. We formalize this challenge as a stochastic gene…
cs.CL2025
Efficient Response Generation Strategy Selection for Fine-Tuning Large Language Models Through Self-Aligned Perplexity
Xuan Ren, Qi Chen, Lingqiao Liu
Fine-tuning large language models (LLMs) typically relies on producing large sets of input-output pairs. Yet for a given question, there can be many valid outputs. In practice, the…