Scatterplot and quantile-quantile (QQ) plots. (a) Typical scatterplot showing increasing levels of differential regulation, together with the 2σ noise envelopes (red lines). There are three different conditions: A, B and C. AA is a duplicate of A. (b) Associated QQ plots of LR/σ (η). The data shown here were obtained using four out of the 12 Mu11KsubA chips used in Figures 1 and 2.