Figure 1.

Empirical density estimates of the t-statistics before and after quantile normalization. Empirical density estimates of the t-statistics before and after quantile normalization. Gene expression are simulated by using normal random numbers with standard deviation 0.35 and gene-gene correlation 0.9. Total number of genes is m = 1000. Total numbers of truly differentially expressed genes are <a onClick="popup('http://www.biomedcentral.com/1471-2105/14/124/mathml/M65','MathML',630,470);return false;" target="_blank" href="http://www.biomedcentral.com/1471-2105/14/124/mathml/M65">View MathML</a> for up-regulated genes and m1- = 40 for down-regulated genes. The sample size is n = 10 and the true effect size is e+ = -e- = e = {0,2,4}. Estimates are based on 200 repetitions.

Qiu et al. BMC Bioinformatics 2013 14:124   doi:10.1186/1471-2105-14-124
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