collaborators

6 papers

cs.LG2025

Learning Intractable Multimodal Policies with Reparameterization and Diversity Regularization

Ziqi Wang, Jiashun Liu, Ling Pan

Traditional continuous deep reinforcement learning (RL) algorithms employ deterministic or unimodal Gaussian actors, which cannot express complex multimodal decision distributions.…

cs.LG2025

Asymmetric Proximal Policy Optimization: mini-critics boost LLM reasoning

Jiashun Liu, Johan Obando-Ceron, Han Lu +7

Most recent RL for LLMs (RL4LLM) methods avoid explicit critics, replacing them with average advantage baselines. This shift is largely pragmatic: conventional value functions are…

cs.LG2025

Part II: ROLL Flash -- Accelerating RLVR and Agentic Training with Asynchrony

Han Lu, Zichen Liu, Shaopan Xiong +19

Synchronous Reinforcement Learning (RL) post-training has emerged as a crucial step for enhancing Large Language Models (LLMs) with diverse capabilities. However, many systems desi…

cs.LG2025

Part I: Tricks or Traps? A Deep Dive into RL for LLM Reasoning

Zihe Liu, Jiashun Liu, Yancheng He +13

Reinforcement learning for LLM reasoning has rapidly emerged as a prominent research area, marked by a significant surge in related studies on both algorithmic innovations and prac…

cs.LG2025

The Courage to Stop: Overcoming Sunk Cost Fallacy in Deep Reinforcement Learning

Jiashun Liu, Johan Obando-Ceron, Pablo Samuel Castro +2

Off-policy deep reinforcement learning (RL) typically leverages replay buffers for reusing past experiences during learning. This can help improve sample efficiency when the collec…

cs.LG2025

Measure gradients, not activations! Enhancing neuronal activity in deep reinforcement learning

Jiashun Liu, Zihao Wu, Johan Obando-Ceron +3

Deep reinforcement learning (RL) agents frequently suffer from neuronal activity loss, which impairs their ability to adapt to new data and learn continually. A common method to qu…