Comparison of the ranking of SNPs. SNPs are ranked by p-value, from 1 (most significant) to least significant, by both the approximate test and the permutation test. Data are genotypes with binary outcomes. The SNP name marked with an asterisk * is the causal SNP, and is the most significant SNP according to both tests. n = 500, m = 20, λ = 1. Only twelve SNPs are shown because the SNPs that were invariant among the sampled individuals were removed from the data before analysis.