Adaptive Gradient-Based Meta-Learning Methods

Mikhail Khodak; Maria-Florina Balcan; Ameet Talwalkar

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arXiv · 1906.02717

Adaptive Gradient-Based Meta-Learning Methods

Mikhail Khodak·Maria-Florina Balcan·Ameet Talwalkar

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Abstract

We build a theoretical framework for designing and understanding practical meta-learning methods that integrates sophisticated formalizations of task-similarity with the extensive literature on online convex optimization and sequential prediction algorithms. Our approach enables the task-similarity to be learned adaptively, provides sharper transfer-risk bounds in the setting of statistical learning-to-learn, and leads to straightforward derivations of average-case regret bounds for efficient algorithms in settings where the task-environment changes dynamically or the tasks share a certain geometric structure. We use our theory to modify several popular meta-learning algorithms and improve their meta-test-time performance on standard problems in few-shot learning and federated learning.

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Mikhail Khodak, Maria-Florina Balcan, Ameet Talwalkar. 2019-12-07. Adaptive Gradient-Based Meta-Learning Methods. https://arxiv.org/abs/1906.02717

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