Sharp Gaussian approximations for Decentralized Federated Learning
- URL: http://arxiv.org/abs/2505.08125v2
- Date: Wed, 22 Oct 2025 19:35:19 GMT
- Title: Sharp Gaussian approximations for Decentralized Federated Learning
- Authors: Soham Bonnerjee, Sayar Karmakar, Wei Biao Wu,
- Abstract summary: Federated Learning has gained traction in privacy-sensitive collaborative environments, with local SGD emerging as a key optimization method.<n>We present two generalized Gaussian approximation results for local SGD and explore their implications.<n>The time-uniform approximations support bootstrap-based tests for detecting adversarial attacks.
- Score: 1.2489632787815885
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Federated Learning has gained traction in privacy-sensitive collaborative environments, with local SGD emerging as a key optimization method in decentralized settings. While its convergence properties are well-studied, asymptotic statistical guarantees beyond convergence remain limited. In this paper, we present two generalized Gaussian approximation results for local SGD and explore their implications. First, we prove a Berry-Esseen theorem for the final local SGD iterates, enabling valid multiplier bootstrap procedures. Second, motivated by robustness considerations, we introduce two distinct time-uniform Gaussian approximations for the entire trajectory of local SGD. The time-uniform approximations support Gaussian bootstrap-based tests for detecting adversarial attacks. Extensive simulations are provided to support our theoretical results.
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