collaborators

7 papers

cs.AI2026

Mahjax: A GPU-Accelerated Mahjong Simulator for Reinforcement Learning in JAX

Soichiro Nishimori, Shinri Okano, Keigo Habara +3

Riichi Mahjong is a multi-player, imperfect-information game characterized by stochasticity and high-dimensional state spaces. These attributes present a unique combination of chal…

cs.LG2026

VI-CuRL: Stabilizing Verifier-Independent RL Reasoning via Confidence-Guided Variance Reduction

Xin-Qiang Cai, Masashi Sugiyama

Reinforcement Learning with Verifiable Rewards (RLVR) has emerged as a dominant paradigm for enhancing Large Language Models (LLMs) reasoning, yet its reliance on external verifier…

cs.LG2026

Positive-Unlabeled Reinforcement Learning Distillation for On-Premise Small Models

Zhiqiang Kou, Junyang Chen, Xin-Qiang Cai +8

Due to constraints on privacy, cost, and latency, on-premise deployment of small models is increasingly common. However, most practical pipelines stop at supervised fine-tuning (SF…

cs.LG2024

Beyond Simple Sum of Delayed Rewards: Non-Markovian Reward Modeling for Reinforcement Learning

Yuting Tang, Xin-Qiang Cai, Jing-Cheng Pang +3

Reinforcement Learning (RL) empowers agents to acquire various skills by learning from reward signals. Unfortunately, designing high-quality instance-level rewards often demands si…

cs.LG2024

Offline Reinforcement Learning from Datasets with Structured Non-Stationarity

Johannes Ackermann, Takayuki Osa, Masashi Sugiyama

Current Reinforcement Learning (RL) is often limited by the large amount of data needed to learn a successful policy. Offline RL aims to solve this issue by using transitions colle…

cs.LG2024

Offline Reinforcement Learning with Domain-Unlabeled Data

Soichiro Nishimori, Xin-Qiang Cai, Johannes Ackermann +1

Offline reinforcement learning (RL) is vital in areas where active data collection is expensive or infeasible, such as robotics or healthcare. In the real world, offline datasets o…