TABLE 4

Robustness to population growth

ModelEmbedded Image Embedded Image ρ/θ in C.I.
10.40.19100
20.60.2499
30.40.2897
  • Shown are the median of the MLE of ρ/θ; g, the proportion of times the MLE is within a factor of 2 of the truth; and coverage properties for the ~95% confidence interval for ρ/θ under population growth. Model 1 has slow exponential growth (population doubling every 20,000 generations to a current size of 10,000). Models 2 and 3 have recent rapid exponential growth from an effective population of 10,000–5,000,000. In model 2 the growth started 1600 generations ago, and in model 3 it started 4000 generations ago. Results are based on 100 samples for each model, with r = μ = 2.5 × 10−5, so the true value of ρ/θ is 1.