Simulations comparing inferred date accuracy and computational speed of fastGLOBETROTTER and GLOBETROTTER. (Top) Inferred admixture dates (+95% CI) for simulations mixing two groups (listed in middle), with the proportion of admixture from the second group given in the x-axis. For each combination of population and admixture proportion, results are given for GLOBETROTTER (GT) and fastGLOBETROTTER (fastGT) for true dates of seven, 30, and 150 generations ago (gray dashed horizontal lines). Sample size (n) for each simulation is given at top. Cases that conclude “no admixture” are depicted with an open square placed at the true date of admixture. Asterisks denote the use of a different grid for binning haplotype segments (see Methods). (Bottom) Computation times (in minutes, excluding bootstrapping used to generate CIs) of each approach for the scenarios above, averaging across the three different admixture dates where applicable.
