Fig. 6.

Probability histograms computed from ${10}^5$ sample paths of the CTMC SIS model show a mixture of two densities when ${\mathrm{ℛ}}_0>1$, the probability of a minor epidemic and the probability of reaching the endemic equilibrium. The overlay curve in red is a graph of $f_{T_3}{\mathrm{\mathbb{P}}}_{\text{ext}}$. Parameter values are $\gamma =1$, $\beta ={\mathrm{ℛ}}_0$ and $N=1000$ with initial conditions $I\left(0\right)=3$ and $S\left(0\right)=997.$