Results for simulated data. The genes are generated independently. Each panel shows the estimated FDR and FNR (solid red and green curves) as well as the 10 and 90th percentiles, using the proposed method (remember that in our setup FDR = 1-power and FNR = type I error). A horizontal line is drawn at 0.05. The quantity on the horizontal axis – number of genes – refers to both the hypothesized number of truly non-null genes, and the number of genes called significant. We see that the FDR is probably too high for the pilot data sample size of 20, but improves considerably when the sample size is doubled to 40.