Figure 2

Impacts of the selection strength β on partial- and free-subsidy policies for large vaccination cost.
For HSWN and c = 0.9, vaccination coverage V (top panels) and epidemic size R (bottom panels) for the two subsidy policies for different values of δ (δ = 0.1, 0.4 and 0.7, corresponding to left, central and right panels, respectively). Other parameters are the same as for Fig. 1.