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arXiv · 1908.06597

Model-free Feature Screening and FDR Control with Knockoff Features

Abstract

This paper proposes a model-free and data-adaptive feature screening method for ultra-high dimensional datasets. The proposed method is based on the projection correlation which measures the dependence between two random vectors. This projection correlation based method does not require specifying a regression model and applies to the data in the presence of heavy-tailed errors and multivariate response. It enjoys both sure screening and rank consistency properties under weak assumptions. Further, a two-step approach is proposed to control the false discovery rate (FDR) in feature screening with the help of knockoff features. It can be shown that the proposed two-step approach enjoys both sure screening and FDR control if the pre-specified FDR level $\alpha$ is greater or equal to $1/s$, where $s$ is the number of active features. The superior empirical performance of the proposed methods is justified by various numerical experiments and real data applications.

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BibTeXRIS

Wanjun Liu, Yuan Ke, Jingyuan Liu, Runze Li. 2019-08-19. Model-free Feature Screening and FDR Control with Knockoff Features. https://doi.org/10.1080/01621459.2020.1783274

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