Title: Adaptively weighted group Lasso for semiparametric quantile regression models
Authors: Toshio Honda - Hitotsubashi University (Japan) [presenting]
Ching-Kang Ing - National Tsing Hua University (Taiwan)
Wei-Ying Wu - National Dong Hwa University (Taiwan)
Abstract: An adaptively weighted group Lasso procedure is proposed for simultaneous variable selection and structure identification for varying coefficient quantile regression models and additive quantile regression models with ultra-high dimensional covariates. Under a strong sparsity condition, we establish selection consistency of the proposed Lasso procedure when the weights therein satisfy a set of general conditions. This consistency result, however, is reliant on a suitable choice of the tuning parameter for the Lasso penalty, which can be hard to make in practice. To alleviate this difficulty, we suggest a BIC-type criterion, which we call high-dimensional information criterion (HDIC), and show that the proposed Lasso procedure with the tuning parameter determined by HDIC still achieves selection consistency. Our simulation studies support strongly our theoretical findings.