Table 1. Results from asymptoticMK for simulation runs conducted with SLiM 2.

Model	αtrue	αasymptotic	αoriginal	Δasymptotic	Δoriginal	ρexp
Baseline	0.329 ± 0.015	0.307 ± 0.058	0.164 ± 0.035	0.045	0.165	0.75
L = 108	0.327 ± 0.008	0.301 ± 0.013	0.174 ± 0.012	0.025	0.152	1.00
L = 106	0.321 ± 0.067	0.246 ± 0.134	0.142 ± 0.141	0.120	0.191	0.15
μ = 10−8	0.306 ± 0.005	0.287 ± 0.016	0.173 ± 0.009	0.019	0.132	1.00
μ = 10−10	0.317 ± 0.057	0.288 ± 0.169	0.145 ± 0.074	0.134	0.173	0.05
rb = 0.0010	0.493 ± 0.018	0.481 ± 0.045	0.378 ± 0.025	0.041	0.114	0.70
rb = 0.0001	0.091 ± 0.014	0.115 ± 0.080	−0.103 ± 0.053	0.071	0.194	0.55
sb = 0.20	0.477 ± 0.016	0.451 ± 0.032	0.366 ± 0.025	0.029	0.111	0.70
sb = 0.02	0.096 ± 0.011	0.090 ± 0.068	−0.119 ± 0.047	0.057	0.215	0.50
sd = −0.200	0.424 ± 0.024	0.422 ± 0.042	0.289 ± 0.036	0.032	0.135	0.60
sd = −0.002	0.233 ± 0.011	0.234 ± 0.057	0.104 ± 0.039	0.045	0.129	0.50
T = 2 × 106	0.324 ± 0.006	0.302 ± 0.014	0.173 ± 0.012	0.022	0.151	1.00
T = 2 × 104	0.345 ± 0.063	0.369 ± 0.183	0.225 ± 0.113	0.126	0.120	0.05

The first row shows the averaged results from 20 replicate runs of the baseline SLiM model supplied on GitHub (see text). These runs used parameter values of mutation rate μ = 10⁻⁹ per base position per generation, chromosome length L = 10⁷ base positions, beneficial mutation rate r_b = 0.0005, beneficial mutation selection coefficient s_b = 0.1, deleterious mutation selection coefficient s_d = −0.02, and time after burn-in T = 2 × 10⁵ generations. Each subsequent row shows the results from 20 replicate runs using the nonbaseline parameter value shown. α_true specifies the true value of α averaged across the 20 replicates in each row; α_asymptotic and α_original specify the asymptoticMK estimate and the estimate from the original test, respectively. SDs across the 20 replicates of each row are shown as ± values. Δ_asymptotic = |α_asymptotic − α_true| and Δ_original = |α_original − α_true| specify the mean absolute errors between true α values and the estimates from asymptoticMK and the original test, respectively, in each run, averaged over the 20 replicates. ρ_exp specifies the fraction of runs in which the exponential fit was chosen.