Fig. 2.

Illustration diagram of the analytical procedure of g-measure calculation. The prevalence time series of 4 different AA substitutions are denoted by p₁(t), p₂(t), p₃(t) and p₄(t), and indicated in red, green, orange and blue, respectively. Three scenarios of dominant prevalence threshold parameter, θ, are demonstrated with θ = 0.5, 0.7, and 0.9, respectively, which is indicated by the horizontal dashed line in each panel. The g-measure counts the segments of the prevalence series that start from 0 and increase over θ. In each panel, the prevalence series that accounts for g-measure is not shaded in grey region. In other words, the shaded regions are those part of prevalence series excluded from the g-measure calculation. For those prevalence series that never excess θ, they are excluded from g-measure calculation as labeled by ‘excluded’; otherwise, ‘included’ label is indicated