Log-likelihood ﹩\mathrm{log}{ \mathcal L }﹩ as a function of fitting parameters ﹩{R}_{0}^{\min }﹩ and ζ, after being marginalized over ﹩{R}_{0}^{\max }﹩, for the standard parameter set γ = −0.9, k = 0.34, and α = −1.5. Confidence intervals of 68%, 90%, 95%, and 99.7% are shown by solid, dashed, dotted–dashed, and dotted lines, respectively.