collaborators

6 papers

cs.IR2026

Rank-GRPO: Training LLM-based Conversational Recommender Systems with Reinforcement Learning

Yaochen Zhu, Harald Steck, Dawen Liang +4

Large language models (LLMs) are reshaping the recommender system paradigm by enabling users to express preferences and receive recommendations through conversations. Yet, aligning…

cs.LG2026

DiFFPO: Training Diffusion LLMs to Reason Fast and Furious via Reinforcement Learning

Hanyang Zhao, Dawen Liang, Wenpin Tang +2

We propose DiFFPO, Diffusion Fast and Furious Policy Optimization, a unified framework for training masked diffusion large language models (dLLMs) to reason not only better (furiou…

cs.IR2025

Does Weighting Improve Matrix Factorization for Recommender Systems?

Alex Ayoub, Samuel Robertson, Dawen Liang +2

Matrix factorization is a widely used approach for top-N recommendation and collaborative filtering. When implemented on implicit feedback data (such as clicks), a common heuristic…

cs.IR2025

From Reviews to Dialogues: Active Synthesis for Zero-Shot LLM-based Conversational Recommender System

Rohan Surana, Junda Wu, Zhouhang Xie +5

Conversational recommender systems (CRS) typically require extensive domain-specific conversational datasets, yet high costs, privacy concerns, and data-collection challenges sever…

cs.LG2025

A Reductions Approach to Risk-Sensitive Reinforcement Learning with Optimized Certainty Equivalents

Kaiwen Wang, Dawen Liang, Nathan Kallus +1

We study risk-sensitive RL where the goal is learn a history-dependent policy that optimizes some risk measure of cumulative rewards. We consider a family of risks called the optim…

cs.IR2025

Collaborative Retrieval for Large Language Model-based Conversational Recommender Systems

Yaochen Zhu, Chao Wan, Harald Steck +4

Conversational recommender systems (CRS) aim to provide personalized recommendations via interactive dialogues with users. While large language models (LLMs) enhance CRS with their…