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arXiv · 2007.15929

On regularization methods based on R\'enyi's pseudodistances for sparse high-dimensional linear regression models

Abstract

Several regularization methods have been considered over the last decade for sparse high-dimensional linear regression models, but the most common ones use the least square (quadratic) or likelihood loss and hence are not robust against data contamination. Some authors have overcome the problem of non-robustness by considering suitable loss function based on divergence measures (e.g., density power divergence, gamma-divergence, etc.) instead of the quadratic loss. In this paper we shall consider a loss function based on the R\'enyi's pseudodistance jointly with non-concave penalties in order to simultaneously perform variable selection and get robust estimators of the parameters in a high-dimensional linear regression model of non-polynomial dimensionality. The desired oracle properties of our proposed method are derived theoretically and its usefulness is illustustrated numerically through simulations and real data examples.

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Elena Castilla, Abhik Ghosh, María Jaenada, Leandro Pardo. 2020-07-31. On regularization methods based on R\'enyi's pseudodistances for sparse high-dimensional linear regression models. https://arxiv.org/abs/2007.15929

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