Evaluation of Principal Components Analyses in East Asian Populations using 200 K SNPs.

aEAS population groups included each of the populations indicated in Figure 1.bThe % eigenvalue (Eigen) is the percentage of the total variance in the first ten PCs.cThe Spearman-Brown split half reliability test (SHT)[39] r2 is the mean+/?SD from the adjusted correlations between: 1) every other chromosomes; 2) half chromosomes (first half each chromosome and second half each chromosome); and 3) first half genome and second half genome (see Methods). These correlations were determined after PCA of each individual set.dThe Kruskal-Wallis test [23], a nonparametric alternative to the ANOVA was used to examine the statistical significance of the difference in PC scores among subject groups pre-assigned based on self-identification.