Distributions of p-values for the paired t-test for hybridization effect. Histograms of p-values for four image processing algorithms. If the global null hypothesis is true, the distribution of p-values would be uniform from 0 to 1 (dotted line). If differentially expressed genes are present, the number of small p-values will be increased.
Zakharkin et al. BMC Bioinformatics 2005 6:214 doi:10.1186/1471-2105-6-214