a)Coefficient of variation (CV) [(SD of M-values × 100)/mean of M-values] was calculated for each series of 48 replicate spots within array before the outliers exclusion. The averages of the seven independent microarray experiments are shown. b) Coefficient of variation (CV) after the exclusion procedure. The CV was calculated as the mean of the remaining data after the filter. c) Percentage of experiments in which the single spike was excluded on a total of seven experiments. The number of experiments in which the specific spike was excluded out of the seven arrays analyzed is shown in parenthesis.