Variable Selection for Nonparametric Learning with Power Series Kernels
Variable Selection for Nonparametric Learning with Power Series Kernels
复制标题
使用幂级数核进行非参数学习的变量选择
DOI:
10.1162/neco_a_01212
复制
发表时间:
2019
影响因子:
2.9
通讯作者:
Kanamori Takafumi
中科院分区:
文献类型:
--
作者:
Matsui Kota;Kumagai Wataru;Kanamori Kenta;Nishikimi Mitsuaki;Kanamori Takafumi
In this letter, we propose a variable selection method for general nonparametric kernel-based estimation. The proposed method consists of two-stage estimation: (1) construct a consistent estimator of the target function, and (2) approximate the estimator using a few variables by-type penalized estimation. We see that the proposed method can be applied to various kernel nonparametric estimation such as kernel ridge regression, kernel-based density, and density-ratio estimation. We prove that the proposed method has the property of variable selection consistency when the power series kernel is used. Here, the power series kernel is a certain class of kernels containing polynomial and exponential kernels. This result is regarded as an extension of the variable selection consistency for the nonnegative garrote (NNG), a special case of the adaptive Lasso, to the kernel-based estimators. Several experiments, including simulation studies and real data applications, show the effectiveness of the proposed method.