Figure 1.

Model definitions. (a) Illustration of a heterogeneous infection pattern (superspreading). Inset shows the probability density function and (one minus) the cumulative probability for the gamma distribution $\mathrm{\Gamma }(R=1.0,k=0.1)$. (b) Likelihood model. The infected individuals whose infection was reported on some day (orange) will themselves infect a number of people. These are in turn detected on other days according to the distribution $p(\mathrm{\Delta }\tau )$. (c) Time scale definitions. ${\tau }_d$ denotes the duration from being infected to being reported, and ${\tau }_i$ the duration between infections (generation time). Finally, $\mathrm{\Delta }\tau$ is the difference between the reported times of infector-infectee pairs. (d) The maximum likelihood of the distributions we employ for ${\tau }_d$ and ${\tau }_i$, and the distribution thus implied for $\mathrm{\Delta }\tau$. $p(\mathrm{\Delta }\tau )$ has support below zero as it is possible that the infector’s infection is reported after the infectee.