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arXiv · 2603.07319

ShakyPrepend: A Multi-Group Learner with Improved Sample Complexity

Lujing Zhang·Daniel Hsu·Sivaraman Balakrishnan
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Abstract

Multi-group learning is a learning task that focuses on controlling predictors' conditional losses over specified subgroups. We propose ShakyPrepend, a method that leverages tools inspired by differential privacy to obtain improved theoretical guarantees over existing approaches. Through numerical experiments, we demonstrate that ShakyPrepend adapts to both group structure and spatial heterogeneity. We provide practical guidance for deploying multi-group learning algorithms in real-world settings.

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Lujing Zhang, Daniel Hsu, Sivaraman Balakrishnan. 2026-03-07. ShakyPrepend: A Multi-Group Learner with Improved Sample Complexity. https://arxiv.org/abs/2603.07319

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