Scatter plot represents the correlation of the results from type 1 and 2 experiments. Genes with expression changes in opposite categories (induction vs. repression) in both approaches are visualized as dots located in the 2nd and 4th quadrants and away from the origin. Pearson's correlation coefficients (r) are indicated in each panel.
Yang et al. BMC Genomics 2008 9(Suppl 2):S5 doi:10.1186/1471-2164-9-S2-S5