Figure 2

The expected folded frequency spectrum in the standard neutral model assuming a sample of size n = 20 chromosomes and an ascertainment sample size of d = 2 (black), d = 5 (dark grey), d = 10 (light grey) and d = 20 (white; no ascertainment bias). In (a) it is assumed that the ascertainment sample is a subset of the typed sample and in (b) it is assumed that it is not.