Comparison of expression estimates on tiling and ATH1 array platforms. Scatter plot of expression estimates in (a) roots and (b) inflorescences. (c) Correlation between expression changes between roots and inflorescences. (d) CAT (correspondence at the top) plot for genes identified differentially expressed in roots and inflorescences. Proportion of genes in common is shown as a function of increasing size of subsets containing the n genes with the highest P values.