Suppose there exists a set of n kinome arrays each containing m different peptides (“probes”). In addition, suppose that there are l within-array replicates (“spots”) for each peptide. In the rest of the paper, the measurements for the kth within-array replicate of the jth peptide on the ith array are denoted by ri,j,k. Variable ri,j,k contains all measurements corresponding to the intensity value of the aforementioned spot. More specifically, it contains foreground and background intensity values, denoted by F(ri,j,k) and B(ri,j,k), respectively. Also, the mean of a peptide is interpreted as the mean of the all background-corrected intensity values for all within-array replicates for that peptide.