What the Biostatistician Needs to Know about Molecular Biology

calculate the t-statistics for each gene in the real data

generate bootstrapped data sets by permuting the

columns (conditions)--preserves dependence

between genes

The highest-ranking gene is up- (down-) regulated, if

for at least 95% (99%) of the bootstrapped

datasets, all genes have a smaller t-value. This

gene is then removed from the set and the

definition is applied recursively until the j-th

ranked gene is no longer deemed to be

differentially regulated.