Current Analytical Methods of DNA Microarray Data - DNA Microarray Technology and Data Analysis in Cancer Research - page 28

Fig. 3.8. Average MA plot of RMA-processed data for sample groups Mut_A
versus B6 (top left), Mut_A versus Vector (top right), and Vector versus B6 (bottom
center).
3.3.2. Transformed intensities across arrays
For each probe set, the processed raw intensities for all probes were
averaged and log 2 -transformed without normalization from Affymetrix's
Expression Console software. The log 2 -transformation of raw data
was used to reduce the impact of outliers and ensure normality (Figs. 3.2
and 3.3).