A Two Sample Test in High Dimensional Data
Muni S. Srivastava, Shota Katayama and Yutaka Kano

Abstract

    In this paper we propose a test for testing the equality of the mean vectors of two groups with unequal covariance matrices based on $N_{1}$ and $N_{2}$ independently distributed $p$-dimensional observation vectors. It will be assumed that $N_{1}$ observation vectors from the first group are normally distributed with mean vector $\bm{\mu}_{1}$ and covariance matrix $\bm{\Sigma}_{1}$. Similarly, the $N_{2}$ observation vectors from the second group are normally distributed with mean vector $\bm{\mu}_{2}$ and covariance matrix $\bm{\Sigma}_{2}$. We propose a test for testing the hypothesis that $\bm{\mu}_{1}=\bm{\mu}_{2}$. This test is invariant under the group of $p\times p$ nonsingular diagonal matrices. The asymptotic distribution is obtained as $(N_{1},N_{2},p)\to\infty$ and $N_{1}/(N_{1}+N_{2})\to k \in (0,1)$ but $N_{1}/p$ and $N_{2}/p$ may go to zero or infinity. It is compared with a recently proposed non-invariant test. It is shown that the proposed test performs the best.

Paper

http://dx.doi.org/10.1016/j.jmva.2012.08.014  (Correction Note)