Figure 4:

Simulation results for confidence interval performance in terms of coverage and width. ${\sigma }_0^2$ is the variance for noise, and ${\sigma }_1^2$ is the variance for the random effect. a - Coverage for heritability confidence interval (CI); simulation was based on true values ${\sigma }_0^2=0.1,{\sigma }_1^2=0.1$. Monte Carlo error of 0.03 is expected for 200 simulation replications. b - Coverage for ${\sigma }_1^2$ CI; simulation was based on true values ${\sigma }_0^2=0.01,{\sigma }_1^2=0.1$. Monte Carlo error of 0.03 is expected for 200 simulation replicates. c - Line charts of median half width of heritability CI with increasing sample sizes; simulation was based on true values ${\sigma }_0^2=0.1,{\sigma }_1^2=0.1$. d - Line charts of median half width of ${\sigma }_1^2$ CI with increasing sample sizes; simulation was based on true values ${\sigma }_0^2=0.01,{\sigma }_1^2=0.1$.