Microarray Data Analysis Using BRB-ArrayTools Version 4.2.0 ...

Efron-Tibshirani's GSA maxmeantest• Tests the null hypothesis that for a gene set the average degreeof differential expression is greater than expected from arandom set of genes.• Uses the maxmean statistic as follows:• Take the di scores for all the genes within a geneset.• Set negative scores to 0 and compute ‘avpos’ as the average ofthe positive scores and zeros.• Similarly set the positive scores to 0 and compute the ‘avneg’as the averages of the negative scores and zeros.• A gene set is scored ‘avpos’ if |avpos| > |avneg| or else thegene set is scored ‘avneg’95