Projection-Free Algorithms in Statistical Estimation

Yan Li; Chao Qu; Huan Xu

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arXiv · 1805.07844

Projection-Free Algorithms in Statistical Estimation

Yan Li·Chao Qu·Huan Xu

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Abstract

Frank-Wolfe algorithm (FW) and its variants have gained a surge of interests in machine learning community due to its projection-free property. Recently people have reduced the gradient evaluation complexity of FW algorithm to $\log(\frac{1}{\epsilon})$ for the smooth and strongly convex objective. This complexity result is especially significant in learning problem, as the overwhelming data size makes a single evluation of gradient computational expensive. However, in high-dimensional statistical estimation problems, the objective is typically not strongly convex, and sometimes even non-convex. In this paper, we extend the state-of-the-art FW type algorithms for the large-scale, high-dimensional estimation problem. We show that as long as the objective satisfies {\em restricted strong convexity}, and we are not optimizing over statistical limit of the model, the $\log(\frac{1}{\epsilon})$ gradient evaluation complexity could still be attained.

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BibTeX RIS

Yan Li, Chao Qu, Huan Xu. 2018-05-20. Projection-Free Algorithms in Statistical Estimation. https://arxiv.org/abs/1805.07844

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