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Statistics Seminar Series
Wednesday, Apr. 17, 2013, 4:00 PM
Cullimore, Room 110
New Jersey Institute of Technology
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Optimal High
Dimensional Multiple Testing Under Linear Models
Jichun Xie
Department of Statistics
Temple University
Abstract
High
dimensional multiple testing has many important applications. Motivated by
genome-wide association studies (GWAS), we consider the problem of multiple
testing under high dimensional sparse linear model in order to identify the
genetic markers associated with the trait of interest. The model is an
extension of the normal mixture model under arbitrary dependence. We propose a
multiple testing procedure, which ranks and thresholds the adjusted
z-surrogate. It is shown that the procedure can control mfdr
level and minimize mfnr level asymptotically among
all the methods based on the original data. Numerical results show that our
method performs well under linear models with correlated predictors. The
procedure is further illustrated through an analysis of a genome-wide
association study in hypertension. At mfdr level
equal to 0.05, it identifies 11 genetic markers associated with systolic blood
pressure and 11 associated with diastolic blood pressure. Many of the markers
are located in the regions associated with human blood pressure based on the
Rat Genome Database.