Relative log expression boxplots for dat1. RLE plots (described in the text) for the total gene signals estimated by different methods. AFE-TGS, AFE-TGS without normalization between arrays. nor75, the AFE-TGS normalized to the 75th percentile. norQ, AFE-TGS normalized by quantiles. norRMAbg, total gene signal estimated by the RMA algorithm using background-corrected probe-level data. norRMA, total gene signal estimated by the RMA algorithm using raw probe-level data without background correction. M, hMSC samples; F, human dermal fibroblast samples.