Figure 8
From: The projection score - an evaluation criterion for variable subset selection in PCA visualization
The effect of the choice of null distribution. (a) The projection score as a function of log10(α), where α is the p-value threshold obtained by applying a two-sided t-test for comparing two artificial sample groups, when 
is defined by assuming all matrix elements are normally distributed. (b) The projection obtained by applying PCA to the most informative variable subset, containing 11 variables.