Normalization methods applied to the human sperm AFX and ILM data. Boxes show the interquartile range and whiskers extend to an additional 1.5 times the interquartile range. Values outside the whiskers are plotted as circles. Notches are drawn such that non-overlapping notches are strong evidence of differing medians [61, 45]. Subtitles show ranking of the methods. Inequalities in sub-titles are significant at the .05/n2 level, where n is the number of methods in each sub-figure (including controls), by two-sided Mann-Whitney U-test. Commas indicate the difference in ranking is not significant. Numbers indicate the number of gene clusters used for XPN, e.g. xpn6 means XPN was performed using 6 gene clusters.