Figure 2.

Numerical test of the heterogeneous SIS model and other ODE approaches. The network has size N ≈ 10⁴, and is scale-free with parameters m₀ = 20 and m = 2. The transmission rate is τ = 1.0 at unit recovery rate. We shift time for each of 10³ stochastic simulations, so all curves agree on when a prevalence of 200 is reached, and the simulation mean and prediction interval can be meaningfully visualized. Clearly, the heterogeneous pairwise approach is in excellent agreement with simulation. Solid line, simulation mean; dashed line, simulation 95% PI; red line, homogeneous pairwise; green line, heterogeneous mixing; blue line, heterogeneous pairwise.