🤖 AI Summary
This work proposes a novel approach to quantile regression under high-dimensional grouped covariates by introducing, for the first time, an adaptive sparse group Lasso penalty that simultaneously incorporates both within-group and between-group sparsity. By integrating adaptive Lasso and adaptive group Lasso penalties, the method effectively captures the dual sparsity structure while preserving the robustness inherent to quantile regression. To enable efficient computation, the authors develop an alternating direction method of multipliers (ADMM) algorithm based on the dual formulation and rigorously establish its global convergence. Extensive experiments on both simulated and real-world datasets demonstrate that the proposed method substantially outperforms existing alternatives, achieving accurate dual sparsity recovery with superior computational efficiency.
📝 Abstract
Sparse penalized quantile regression provides an effective framework for variable selection and robust estimation in high-dimensional data analysis. When ex planatory variables are organized into groups, achieving sparsity both within and between groups is essential. However, existing quantile regression methods often fail to meet this dual objective. To address this gap, we introduce the adaptive sparse group lasso penalized quantile regression, which integrates adaptive lasso and adaptive group lasso penalties. We optimize the model parameters via the alternating direction method of multipliers (ADMM) applied to the dual problem, and establish global convergence. Through extensive simulation studies and real data analyses, we demonstrate (i) the efficacy of the proposed method in achieving simultaneous within- and between-group sparsity, and (ii) the computational efficiency of our algorithm relative to existing alternatives.