Federated $\mathcal{X}$-armed Bandit with Flexible Personalisation
This work addresses the challenge of balancing personalization and collective learning in heterogeneous federated settings, with applications in domains like healthcare and e-commerce.
The paper tackles the problem of optimizing both local and global objectives in personalized federated learning within the X-armed bandit framework, achieving sublinear regret with logarithmic communication overhead.
This paper introduces a novel approach to personalised federated learning within the $\mathcal{X}$-armed bandit framework, addressing the challenge of optimising both local and global objectives in a highly heterogeneous environment. Our method employs a surrogate objective function that combines individual client preferences with aggregated global knowledge, allowing for a flexible trade-off between personalisation and collective learning. We propose a phase-based elimination algorithm that achieves sublinear regret with logarithmic communication overhead, making it well-suited for federated settings. Theoretical analysis and empirical evaluations demonstrate the effectiveness of our approach compared to existing methods. Potential applications of this work span various domains, including healthcare, smart home devices, and e-commerce, where balancing personalisation with global insights is crucial.