Terry Speed Division of Bioinformatics, The Walter & Eliza Hall Institute of Medical Research Department of Statistics, University of California at Berkeley Location: Carslaw 173 Time: 2pm Friday, May 14, 2010 Title: Correcting for Unwanted Variation in Microarray Data Abstract: Principal components have been used a lot with microarray data to exhibit unwanted variation, and to some extent to remove such variation. Such efforts are also called normalization. In this talk I will review some of these methods, and related work, and propose a simple but apparently novel variant which works a lot of the time, though not always. Part of my story will be a discussion of how one tells whether one is helping or hurting the analysis by adjusting. Joint work with Johann Gagnon-Bartsch