TABLE 5.

Estimating heritability for a normally distributed trait with varying sample size: "Npairs" is the number of MZ and DZ twin pairs (e.g. Npairs=50 means there were 50 MZ twin pairs and 50 DZ twin pairs). In each setting, the average estimated heritability (outside the parentheses) is reported across 1000 simulated datasets. In parentheses: true standard error (standard deviation of estimates across all simulation replicates), average estimated standard error, and 95% confidence interval coverage rate. The true h² = 0.5, c² = 0.3, e² = 0.2.

Npairs	NACE	GEE2-NACE	Falconer	GEE2-Falconer
50	0.50 (0.18, 0.18, 0.89)	0.50 (0.19, 0.19, 0.92)	0.51 (0.23, 0.16, 0.82)	0.51 (0.23, 0.22, 0.93)
100	0.50 (0.14, 0.13, 0.94)	0.50 (0.14, 0.13, 0.94)	0.50 (0.16, 0.11, 0.84)	0.50 (0.16, 0.15, 0.95)
200	0.50 (0.10, 0.10, 0.95)	0.50 (0.10, 0.10, 0.95)	0.50 (0.11, 0.08, 0.84)	0.50 (0.11, 0.11, 0.94)
400	0.50 (0.07, 0.07, 0.94)	0.50 (0.07, 0.07, 0.94)	0.50 (0.08, 0.06, 0.83)	0.50 (0.08, 0.08, 0.94)