Probability density of extinction prehistory and the optimal path to extinction for Model 2.

<p>The red point denotes the endemic state. A simulation starts with the population at the endemic state and stops when the number of infected individuals is zero. The probability density uses the last five years of data from 200,000 Monte Carlo extinction realizations.The parameters are year⁻¹, year⁻¹, , and people. Red colors correspond to regions of highest frequency for the path to extinction. The optimal path (white curve) is computed from the Hamiltonian model and connects the endemic state to the extinct state. Notice that it lies on the peak of the probability density of extinction prehistory.