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arXiv · 2507.22277

Parallel block coordinate descent methods with identification strategies

Ronaldo Lopes·Sandra A. Santos·Paulo J. S. Silva
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Abstract

This work presents a parallel variant of the algorithm introduced in [Acceleration of block coordinate descent methods with identification strategies Comput. Optim. Appl. 72(3):609--640, 2019] to minimize the sum of a partially separable smooth convex function and a possibly non-smooth block-separable convex function under simple constraints. It achieves better efficiency by using a strategy to identify the nonzero coordinates that allows the computational effort to be focused on using a nonuniform probability distribution in the selection of the blocks. Parallelization is achieved by extending the theoretical results from Richt\'arik and Tak\'a\v{c} [Parallel coordinate descent methods for big data optimization, Math. Prog. Ser. A 156:433--484, 2016]. We present convergence results and comparative numerical experiments on regularized regression problems using both synthetic and real data.

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Ronaldo Lopes, Sandra A. Santos, Paulo J. S. Silva. 2025-07-29. Parallel block coordinate descent methods with identification strategies. https://arxiv.org/abs/2507.22277

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