medianNormalise {beadarray} | R Documentation |
Normalizes expression intensities so that the intensities or log-ratios have equal median values across a series of arrays.
medianNormalise(BLData)
BLData |
can be either an BeadLevelList object or an BeadSummaryList object. |
Normalization is intended to remove from the expression measures any systematic trends which arise from the microarray technology rather than from differences between the probes or between the target RNA samples hybridized to the arrays.
For median normalisation, the intensity for each gene is adjusted by subtracting the median of all genes on the array and then adding the median across all arrays. The effect is that each array then has the same median value.
Produces an BeadLevelList containing normalised intensity values. Values will be on the log2 scale
Mark Dunning
data(BLData) BLData.med = medianNormalise(BLData) #All distributions are fixed to have same median boxplot(BLData.med$R~col(BLData.med$R))