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arXiv · 1306.5386

A Second-Order Method for Strongly Convex L1-Regularization Problems

Kimon Fountoulakis·Jacek Gondzio
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Abstract

In this paper a robust second-order method is developed for the solution of strongly convex l1-regularized problems. The main aim is to make the proposed method as inexpensive as possible, while even difficult problems can be efficiently solved. The proposed approach is a primal-dual Newton Conjugate Gradients (pdNCG) method. Convergence properties of pdNCG are studied and worst-case iteration complexity is established. Numerical results are presented on synthetic sparse least-squares problems and real world machine learning problems.

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Kimon Fountoulakis, Jacek Gondzio. 2013-06-23. A Second-Order Method for Strongly Convex L1-Regularization Problems. https://arxiv.org/abs/1306.5386

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