Bootstrap estimates of the p -values under the alternative hypothesis H
: γ 0. For each value of the rate ratio f=ρ/ρ, 100 data sets with sample sizes of n=20 and n=35 haplotypes, respectively, are independently generated using the MS program  with a mutation rate ρ=1.0/kb and a mean tract length ρ=0.5 kb. The first five sub-figures show the Q-Q plots of the bootstrap p-values (B=200) versus a uniform distribution. The last sub-figure plots the power of the test when using 0.05 as a p-value threshold.