Shortcuts in Small World Model

Cascade spreading in a two-dimensional 50 x 50 grid with periodic boundary conditions and random shortcut links - loosely reminding of spatial epidemic spreading with air traffic and healing costs, but no immunity

Red nodes are infected, green nodes are healthy. Additional shortcut links are shown in blue. Most nodes have 4 direct neighbours, while a few of them possess an additional directed random connection to a distant node. The spontaneous infection rate is s=0.001 per time step, the infection rate by an infected neighbouring node is p=0.1. Recovery occurs with a rate q=0.4, if there is enough budget b greater than 0 to bear the healing costs c of 80.