(Figure 1a) or rβ=0.7 (Figure 1b); we set the correlation in estimation error between every pair of traits to rε=0 in these simulations. The figure shows that inflation increases roughly linearly in the number of traits. The bias is larger when the GWASs are lower powered and when rβ is smaller. Our application to DEP, NEUR, and SWB (discussed below) corresponds roughly to a mean χ2-statistic of 1.4 with T=3 in Figure 1b. In that setting, inflation is negligible. Even when inflation is largest—the low-powered GWAS with T=20 in Figure 1a—it is only 3%.
