Boxplots of the distributions of non-normalized M values for microarrays in the five studies. In each boxplot, the box depicts the main body of the data and the whiskers show extreme values. The variability is indicated by the size of the box and the length of the whiskers (marray/marraymaBoxplot(y="maM")). Each panel in the left-hand column shows results for M values at the local level of a microarray chosen at random from a given data set. The bars are color-coded by PT group. Each panel in the right-hand column shows results for M values at the global level for 50 microarrays chosen at random from a given data set (the total number of microarrays in RENAL CELL CARCINOMA is 38). Each row corresponds to a particular study.