arXiv Machine Learning

Sense Once, Serve Many: Common-Trace Factorized Constrained PPO for Online Sensing-Session Consolidation in Multi-Tenant ISAC Networks

The paper introduces Common-Trace Factorized Constrained Proximal Policy Optimization (CT‑PPO) for optimizing online sensing‑session consolidation in multi‑tenant integrated sensing and communication (ISAC) networks. By formulating the problem as a constrained Markov decision process, CT‑PPO shares workload traces across stochastic policy replicas and uses leave‑one‑out discounted Monte Carlo returns to credit applicable actor factors, achieving higher macro returns and lower sensing‑resource costs than baseline methods. Ablation studies show that the common‑trace reward credit is the key contributor to performance gains, and the algorithm retains advantages across varying arrival loads without increasing deployment latency.

arXiv Machine Learning
Oct 2

VERA: Verifiable Feasibility Representations with Counterfactual Credit for Constrained Multi-Agent Control

VERA is a centralized‑training, decentralized‑execution framework for constrained multi‑agent control that separates feasibility estimation from credit assignment. Each actor predicts a five‑dimensional verifiable feasibility representation (VFR), which is supervised by exact action‑conditioned margins during training and ranked by a counterfactual group‑relative advantage (CGRA). In a dynamic space‑air‑ground integrated network, VERA achieves over 55% success with minimal coverage violation, outperforming baselines by up to 8.74 percentage points and reducing violations by more than 50%.

By Bo Yin, Dongbo Li, Hongkai Chen, Jie Liu, Guoliang Xing
arXiv Machine Learning
Aug 11

CODS: Iterative Bellman-Residual Data Selection for Reusable Offline Reinforcement Learning

arXiv:2608. 07719v1 Announce Type: new Abstract: Offline reinforcement learning repeatedly trains policies from a fixed transition pool, making redundant data costly across seeds and hyperparameters, while naive subsampling can remove rare transitions needed for long-horizon credit assignment.

By Ibne Farabi Shihab, Sanjeda Akter, Abu Sa-Adat Mohamed Moon-Im Al Ahsan, Md Najmus Swaqeeb, Anuj Sharma
arXiv Machine Learning
Jul 13

SafeExplorer: An Unbiased Policy Gradient for Reinforcement Learning with Recovery Interventions

arXiv:2607. 08925v1 Announce Type: new Abstract: Training reinforcement-learning agents directly on physical robots makes every fall costly, since a fall can damage the platform and cannot be undone like a simulator reset; the goal is therefore to minimize falls during training rather than trade them off against return, as constrained Markov decision process (MDP) formulations do.

By Elham Daneshmand, Majid Khadiv, Glen Berseth, Hsiu-Chin Lin
arXiv Machine Learning
Oct 8

COPC: Coupled Off-Policy Correction for Asynchronous LLM Reinforcement Learning

The paper introduces COPC, a Coupled Off-Policy Correction method for asynchronous reinforcement learning of large language models. COPC coordinates policy-side and advantage-side corrections by combining token-level ratio masking with two-sided clipped-ratio weighting of TD residuals, addressing both policy mismatch and advantage staleness. Experiments show COPC outperforms existing asynchronous baselines on tool-integrated mathematical reasoning and search tasks, while maintaining training stability and minimal overhead.

By Zicheng Hu, Zhijian Zhou, Xuan Zhang, Yuchen Liu, Cheng Chen, Yuan Li, Qi Gu, Yan Feng, Hongyan Hao, Chao Qu
arXiv Machine Learning
Oct 3

Reusing Past Samples in Proximal Policy Optimization: When and How Does It Help?

The paper investigates how reusing past samples can improve the sample efficiency of Proximal Policy Optimization (PPO). Two variants, wPPO-U and wPPO-BH, are introduced within a multiple importance weighting framework, each reusing data from recent iterations while preserving core PPO mechanics. The authors derive theoretical policy improvement bounds for both variants and empirically evaluate their impact on continuous control tasks.

By Alessandro Montenegro, Riccardo Venturelli, Marco Mussi, Matteo Papini, Alberto Maria Metelli
arXiv AI
Sep 15

ReCAST: Reward Credit Assignment across Timesteps for Online Diffusion Reinforcement

ReCAST is a method for assigning credit to multiple rewards during diffusion model training by using a reward-by-timestep weight matrix that respects user-specified reward budgets while ensuring equal total weight per denoising step. It allocates weight based on each reward’s informativeness, measured by its Rényi discriminability gain at each step, allowing rewards to contribute more when they are most informative. Experiments on SD3.5‑Medium with two four‑reward settings show that ReCAST improves or matches training rewards, enhances held‑out judges, and is preferred by an independent LLM‑as‑a‑Judge, indicating generalizable benefits.

By Yihang Chen, Yuanhao Ban, Kuei-Chun Kao, Cho-Jui Hsieh