I need to normalize and Shift to 75.0 percentile, I used limma package, a part of my code is: RG <- read.maimages(my.filenames, source="agilent", columns=one.col, dec=".") MA <- backgroundCorrect(RG) MAnorm <- normalizeBetweenArrays(MA$G, method="quantile") But In the normalization function I don't known where write that Shifted to 75.0 percentile or how to make this? Help me please, Paz [[alternative HTML version deleted]]