Reinforcement learning

Policy optimisation, reward modelling and RLHF — how models are trained by feedback rather than by labels.

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arXiv AI
Oct 7

Foundation Model-Aided Multi-Agent Reinforcement Learning for Wireless Random Access Network Optimization

The paper introduces a foundation model–aided actor‑critic algorithm to boost multi‑agent reinforcement learning (MARL) for optimizing random access (RA) wireless networks. By embedding a foundation model into a consensus‑based decentralized MARL framework, the authors provide convergence analysis that matches conventional MARL under local reward exchanges and nonlinear value function approximations. Numerical experiments demonstrate that this FM‑based approach markedly accelerates MARL training for RA network optimization.

By Myeung Suk Oh, Zhiyao Zhang, Alvaro Velasquez, Nathaniel D. Bastian, Jia Liu
arXiv Machine Learning
Oct 7

Learning from Unreliable Trajectories: Adversarially-Robust Federated Q-Learning

The paper introduces Robust Async-Fed-Q, an epoch‑based federated Q‑learning algorithm that combines variance‑reduced Bellman operator estimation with robust server aggregation. It provides high‑probability finite‑time guarantees showing that honest agents retain sample‑efficiency benefits even when some agents act adversarially, with the adversarial impact diminishing as honest data grows. The authors also present matching lower bounds, extend the framework to single‑trajectory sampling and heterogeneous coverage, and improve communication complexity for asynchronous federated Q‑learning.

By Sreejeet Maity, Aritra Mitra
arXiv Machine Learning
Oct 7

Common-Mode Errors Limit Low-Timestep Deep Spiking Q-Networks

The paper identifies that low‑timestep deep spiking Q‑networks (DSQNs) suffer mainly from common‑mode errors that degrade Q‑value estimation. To address this, the authors introduce Common‑Mode Compensation DSQN (CMC‑DSQN), which employs an auxiliary ANN during training to correct these errors while keeping inference energy‑efficient. Experiments on Atari and MiniAtar show that CMC‑DSQN improves performance by nearly 20 % at two timesteps and outperforms both DSQN baselines and the ANN baseline at four timesteps.

By Zijie Xu, Bingrui Guo, Yiding Sun, Yiting Dong, Zhile Yang, Zhaofei Yu
arXiv Machine Learning
Oct 7

QF3: Fast Flow RL with Filtered Q-Gradients

QF3 (Fast Flow RL with Filtered Q-Gradients) is an online off‑policy reinforcement learning algorithm that trains flow policies by combining flow matching with the critic’s action gradient, backpropagated through a one‑step prediction of the flow output. It selectively applies the critic gradient only to action dimensions close to the replay action to ensure reliable updates. QF3 is the first off‑policy flow RL method to train humanoid locomotion policies from scratch and transfer them zero‑shot to hardware, achieving a 10× wall‑clock speedup over the on‑policy FPO++ method, and it can also fine‑tune pretrained flow‑based manipulation policies on ABC‑Sim and Robomimic tasks.

By Chung Min Kim, Brent Yi, David McAllister, Hongsuk Choi, Himanshu Gaurav Singh, Jinkun Cao, Ken Goldberg, Pieter Abbeel, Carmelo Sferrazza, Angjoo Kanazawa
arXiv AI
Oct 7

Can Agents Work for Everyone? Cross-User Reliability for Mobile GUI Agents in Personalized User Interfaces

The paper introduces PAIR, a pipeline that creates user-conditioned application states to evaluate mobile GUI agents across different users, and RePAIR, a reinforcement learning method that incorporates personalization-aware interaction rewards. Experiments with six agents reveal significant variability in task success and subgoal achievement across users, especially when targeting personal content. RePAIR improves success rates over supervised fine-tuning, suggesting that learning from cross-user differences can enhance GUI-agent reliability.

By Yeji Park, Jaeyun Shim, Taesik Gong
arXiv AI
Oct 7

SIGMA: Self-Improving Alignment Generalization from a Model Spec

SIGMA is a self‑improving alignment framework that uses a model’s own reasoning to generate diverse alignment dilemma scenarios from a simple "Model Spec" and then fine‑tunes the model with self‑judged rewards. By performing spec‑guided task synthesis and rubric‑based reinforcement learning, SIGMA improves safety alignment in multi‑turn agentic settings, reducing harmfulness and misalignment scores while preserving general capability. The approach demonstrates that a model can autonomously strengthen its own safety reasoning without external supervision.

By Jingyu Zhang, Shruti Palaskar, Daniel Khashabi, Benjamin Van Durme, Leon A. Gatys, Joseph Yitan Cheng
arXiv AI
Oct 7

Beyond Scalar IoU: Structured Verification from Rollout Groups for Video Temporal Grounding

The paper introduces SUTURE, a structured verification method for video temporal grounding that leverages the joint structure of rollout groups rather than scoring each rollout independently. SUTURE conditions verification on the entire rollout group, using disagreement across rollouts to reweight targets and coverage at each position to redistribute reward mass. Experiments on five benchmarks show that SUTURE consistently improves grounding performance across all IoU thresholds and reduces video-start anchoring in reasoning traces, indicating that the joint structure of a rollout group can provide a more informative temporal verifier.

By Youngjae Cho, Won Young Jhoo, Jongsuk Kim
arXiv AI
Oct 7

BluffJAX: Adversarial Imperfect Information Games in JAX

BluffJAX is an open‑source suite of adversarial imperfect‑information games implemented in JAX, designed for high‑throughput simulation and GPU parallelization. It includes classic benchmarks like Texas Hold’Em and Kuhn Poker, as well as newer games such as Bluff, Stud Poker, and Kemps, aiming to broaden research in game‑theoretic reinforcement learning. The authors benchmarked throughput, memory usage, and algorithmic performance across single and multi‑GPU setups, showing scalability to hundreds of millions of samples per second and providing baseline results for future work.

By Aryaman Reddi, Jan Peters, Carlo D'Eramo
arXiv AI
Oct 7

Learning in Dreams, Winning in Reality: A Continuous Dyna Loop for a Ten-Hero MOBA

The paper presents a continuous Dyna loop that trains a multi‑agent world model for a ten‑hero MOBA game and evaluates the resulting policy in the real game. By using imagined episodes and real‑game data to continuously refine the model, the policy achieves a 70.2% win rate as radiant on unseen seeds, a dramatic improvement over dream‑only training. The study highlights that internal dream metrics can miss model exploitation, that the world model must be repaired on the policy’s own games, and that the policy’s success stems from macro‑level pressure rather than precise micro‑tactics.

By Jordy Kieto
arXiv AI
Oct 7

Beyond Refusal Patterns: Safe-Role Internalization for Robust and Generalizable LLM Safety Alignment

The paper introduces SSRFT (Supervised Safe-Role Fine‑Tuning), a new framework that reframes safety alignment for large language models as internalizing a predefined safe role rather than relying on explicit refusal patterns. SSRFT builds a Safe‑Role Question‑Answer dataset from psychometric questions, limited jailbreak prompts, and a safe‑role description, then synthesizes and validates role‑consistent responses to expose models to diverse safety scenarios. Experiments on multiple base and instruct models demonstrate that SSRFT yields more robust and generalizable safety alignment, better resilience to prefilling attacks, improved generalization to unseen jailbreak domains, and reduced over‑refusal on benign queries while preserving general capabilities.

By Jinghao Pang, Jitai Hao, Qiang Huang, Zhaochun Ren, Jun Yu
arXiv AI
Oct 7

Aligning LLMs with Biomedical Knowledge using Balanced Fine-Tuning

arXiv:2511.21075v4 Announce Type: replace-cross Abstract: Engineering LLMs to accelerate life sciences research requires a robust alignment with biomedical knowledge. We observe that biomedical text...

By Zhenchao Tang, Fang Wang, Haohuai He, Jiale Zhou, Tianxu Lv, Jun Zhu, Shouzhi Chen, Minghao Yang, Yu Wang, Jiayang Wu, Yidong Song, Yaokun Li, Jiehui Huang, Jun Zhou, Bing He, Jianhua Yao