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arXiv · 2103.16232

Linearly-constrained nonsmooth optimization for training autoencoders

Wei Liu·Xin Liu·Xiaojun Chen
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Abstract

A regularized minimization model with $l_1$-norm penalty (RP) is introduced for training the autoencoders that belong to a class of two-layer neural networks. We show that the RP can act as an exact penalty model which shares the same global minimizers, local minimizers, and d(irectional)-stationary points with the original regularized model under mild conditions. We construct a bounded box region that contains at least one global minimizer of the RP, and propose a linearly constrained regularized minimization model with $l_1$-norm penalty (LRP) for training autoencoders. A smoothing proximal gradient algorithm is designed to solve the LRP. Convergence of the algorithm to a generalized d-stationary point of the RP and LRP is delivered. Comprehensive numerical experiments convincingly illustrate the efficiency as well as the robustness of the proposed algorithm.

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Wei Liu, Xin Liu, Xiaojun Chen. 2021-03-30. Linearly-constrained nonsmooth optimization for training autoencoders. https://arxiv.org/abs/2103.16232

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