Fig. 7.

Computation of the transit probabilities in a toy example. Let $p_i$ be the probability that an individual, starting in $X_1$, will transit through state $X_i$. We assume transitions between state $X_i$ and state $X_j$ occur at a rate $k_{ij}$ and that the possible transmissions are given in the graph shown in this figure. Then, $p_1=1$, $p_2=p_1$, $p_3=p_2{k}_{23}/(k_{23}+k_{26})$, $p_4=p_3{k}_{34}/(k_{34}+k_{35})$, $p_5=p_3-p_4$, $p_6=p_2-p_3$, $p_7=p_6$.