Linear screening for high-dimensional computer experiments

Chunya Li; Daijun Chen; Shifeng Xiong

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arXiv · 2006.07640

Linear screening for high-dimensional computer experiments

Chunya Li·Daijun Chen·Shifeng Xiong

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Abstract

In this paper we propose a linear variable screening method for computer experiments when the number of input variables is larger than the number of runs. This method uses a linear model to model the nonlinear data, and screens the important variables by existing screening methods for linear models. When the underlying simulator is nearly sparse, we prove that the linear screening method is asymptotically valid under mild conditions. To improve the screening accuracy, we also provide a two-stage procedure that uses different basis functions in the linear model. The proposed methods are very simple and easy to implement. Numerical results indicate that our methods outperform existing model-free screening methods.

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Chunya Li, Daijun Chen, Shifeng Xiong. 2020-06-13. Linear screening for high-dimensional computer experiments. https://arxiv.org/abs/2006.07640

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