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arXiv · 2607.10571

Learning from Local Walks on Dynamic Graphs with Bandit Feedback

Abstract

We study stochastic multi-armed bandits on dynamic graphs, where arms correspond to the vertices of a network with time-varying edges. In this setting, the learner is restricted to local movement, selecting only its current node or an immediate neighbor at each round. This constraint decouples best-arm identification from exploitation: even after the optimal arm is identified, the learner may remain unable to reach it through the evolving topology. We identify a process-agnostic structural condition, based on sliding-window mixing, that ensures the graph's intrinsic walk remains stable for both exploration and navigation. Under this regime, we analyze a family of local explore-then-commit algorithms and establish sublinear expected regret. Our framework includes a reward-aware strategy, for which we prove a worst-case safety theorem and a separate performance gain theorem.

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BibTeXRIS

Sourav Chakraborty, Amit Kiran Rege, Claire Monteleoni, Lijun Chen. 2026-07-27. Learning from Local Walks on Dynamic Graphs with Bandit Feedback. https://arxiv.org/abs/2607.10571

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