 TCGA Affymetrix U000A and Agilent G0000A data sets.](pone.0000000.g000){#pone-0000000-g000}  ![Source of variation of expression profiles of all genes in the REMBRANDT data set.\ The x-axis shows the components of the 0-way ANOVA model and the y-axis shows the median signal to noise ratio. The ANOVA model is built based on the expression profiles of all genes in 