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arXiv · 1803.02246

Rest-Katyusha: Exploiting the Solution's Structure via Scheduled Restart Schemes

Junqi Tang·Mohammad Golbabaee·Francis Bach·Mike Davies
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Abstract

We propose a structure-adaptive variant of the state-of-the-art stochastic variance-reduced gradient algorithm Katyusha for regularized empirical risk minimization. The proposed method is able to exploit the intrinsic low-dimensional structure of the solution, such as sparsity or low rank which is enforced by a non-smooth regularization, to achieve even faster convergence rate. This provable algorithmic improvement is done by restarting the Katyusha algorithm according to restricted strong-convexity constants. We demonstrate the effectiveness of our approach via numerical experiments.

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Junqi Tang, Mohammad Golbabaee, Francis Bach, Mike Davies. 2018-03-06. Rest-Katyusha: Exploiting the Solution's Structure via Scheduled Restart Schemes. https://arxiv.org/abs/1803.02246

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