Results of testing different combinations of analysis methods. (a) Numbers of genes reaching a 99% confidence level in all possible combinations of normalization and statistical analysis algorithms. x-axis, normalization methods; y-axis, statistical analysis algorithms. Column height, number of genes. (b) Percentage of genes from Figure 2a that additionally reach a ratio of at least 2 and an absolute difference of at least 100 units. Layout is as in Figure 2a. AD, average difference; F, F-statistics; KW, Kruskal-Wallis; MBEV, model-based expression values; significance analysis of microarrays (SAM).