Table 1. Type l error rates of different methods with the Freesurfer trait correlation matrix.

α	5 × 102	1 × 102	1 × 104	1 × 106	5 × 107	5 × 108
SUM	5.0 × 10−2	1.0 × 10−2	1.0 × 10−4	9.7 × 10−7	5.2 × 10−7	4.5 × 10−8
SSU	4.6 × 10−2	1.0 × 10−2	1.8 × 10−4	3.5 × 10−6a	2.0 × 10−6a	2.7 × 10−7a
Chi-squared	4.7 ×10−2	1.0 × 10−2	1.7 × 10−4a	4.3 × 10−6a	2.6 × 10−6	4.9 × 10−7a
Hom	5.6 × 10−1a	4.5 × 10−1a	2.5 × 10−1a	1.5 × 10−1a	1.4 × 10−1a	1.1 × 10−1a
MAT(1)	5.0 × 10−2	1.0 × 10−2	1.0 ×10−4	9.8 ×10−7	4.8 ×10−7	4.8 ×10−8
MAT(10)	5.0 × 10−2	1.0 × 10−2	1.0 ×10−4	1.0 × 10−6	4.9 ×10−7	4.5 × 10−8
MAT(30)	5.0 × 10−2	1.0 × 10−2	1.0 ×10−4	1.0 × 10−6	5.2 × 10−7	5.4 × 10−8
MAT(50)	5.0 × 10−2	1.0 × 10−2	9.9 × 10−5	9.6 × 10−7	4.4 × 10−7	4.6 × 10−8
aMAT	4.7 × 10−2	9.4 × 10−3	9.5 × 10−5	1.1 × 10−6	5.5 × 10−7	4.7 × 10−8

We simulated 1 billion (1 × 10⁹) replications under the null and estimated Type l error rates as the proportions of P-values less than significance level α.

^aInflated Type l error rates.