arXiv Machine Learning

Flow Matching Policy Optimization with Mirror Descent and Entropy Constraints

arXiv AI
Oct 1

Diffusion-Augmented Markov Decision Processes for Maximum Entropy Reinforcement Learning

The paper introduces Diffusion-Augmented Markov Decision Processes (DA‑MDPs), a framework that extends Maximum Entropy Reinforcement Learning to diffusion-based policies. DA‑MDPs treat each reverse‑diffusion step as an RL decision, deriving a tractable reverse‑KL bound that decomposes across denoising transitions and yields diffusion‑augmented soft rewards, value functions, and policy objectives. The authors implement this framework with PPO, REPPO, and a maximum‑entropy WPO variant, showing improved continuous‑control performance, higher success rates on manipulation tasks, and memory‑efficient training with action chunking.

By Sebastian Sanokowski, Kaustubh Patil, Majid Khadiv
arXiv AI
Oct 12

Stochastic MeanFlow Policies: One-Step Generative Control with Entropic Mirror Descent

The paper introduces Stochastic MeanFlow Policies (SMFP), a one‑step generative policy class that merges MeanFlow noise‑to‑action mappings with Gaussian reparameterisation. SMFP captures diverse action modes while providing an analytic entropy lower bound through a learnable conditional Gaussian scale, enabling entropy‑regularised mirror‑descent learning. Experiments on seven MuJoCo benchmarks show SMFP outperforming Gaussian and generative baselines, and additional tests demonstrate effective multimodal action modelling and exploration in sparse‑reward navigation.

By Zeyuan Wang, Da Li, Yulin Chen, Yuehu Gong, Yanming Guo, Liang Bai, Tianyuan Yu, Yanwei Fu
arXiv Machine Learning
Jul 20

Dichotomous Diffusion Policy Optimization

arXiv:2601. 00898v3 Announce Type: replace Abstract: Diffusion-based policies have gained growing popularity in solving a wide range of decision-making tasks due to their superior expressiveness and controllable generation during inference.

By Ruiming Liang, Yinan Zheng, Kexin Zheng, Tianyi Tan, Jianxiong Li, Liyuan Mao, Zhihao Wang, Guang Chen, Hangjun Ye, Jingjing Liu, Jinqiao Wang, Xianyuan Zhan
arXiv Machine Learning
19h ago

Doob-Based Generative Policy Optimization

Doob-Based Generative Policy Optimization (DoobPO) introduces a likelihood‑free framework for fine‑tuning generative policies such as diffusion and flow models. It first learns a lightweight ratio model to represent the desired policy update and then distills this ratio‑tilted target policy into the generative policy via conditional drift matching. The method supports standard policy improvement rules like PPO and GRPO, proves gradient equivalence to an ideal Doob drift matching objective, and demonstrates strong performance on MuJoCo continuous‑control benchmarks.

By Maojiang Su, Qijie Zhu, Yu Xiao, Shuyang Yu, Minshuo Chen, Zhaoran Wang, Han Liu