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Title: Federated Learning under Distributed Concept Drift
Federated Learning (FL) under distributed concept drift is a largely unexplored area. Although concept drift is itself a well-studied phenomenon, it poses particular challenges for FL, because drifts arise staggered in time and space (across clients). Our work is the first to explicitly study data heterogeneity in both dimensions. We first demonstrate that prior solutions to drift adaptation, with their single global model, are ill-suited to staggered drifts, necessitating multiple-model solutions. We identify the problem of drift adaptation as a time-varying clustering problem, and we propose two new clustering algorithms for reacting to drifts based on local drift detection and hierarchical clustering. Empirical evaluation shows that our solutions achieve significantly higher accuracy than existing baselines, and are comparable to an idealized algorithm with oracle knowledge of the ground-truth clustering of clients to concepts at each time step.  more » « less
Award ID(s):
2107024 2045694
NSF-PAR ID:
10462958
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Artificial Intelligence and Statistics Conference (AISTATS)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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