Dynamical cascades in geographical networks with socio-economic gravity-based weights

The number of people living in cities is expected to rise over the coming years. In parallel, managing the adverse effects of urbanization is becoming much more crucial, specifically the impact of geographical flows. The study utilizes the complexity perspective and presents the use of a discrete cascade model to examine the underlying urban form and to serve as a basis for studying geographical flows. Building data from four cities of the Metro Manila conurbation are used, which are selected to cover various urban characteristics. A city is partitioned through the Voronoi areas of its buildings, and a network is generated with the building points serving as the nodes. The edges are constructed based on the actual adjacency of the building\u27s Voronoi areas, i.e., two nodes are connected if the Voronoi cells of their buildings are next to each other. Weights are given based on a variation of the gravity model to proxy socioeconomic interactions among the cells. Next, sandpile rules are applied over the network to model cascades, with the threshold of each site set according to their Voronoi cell area. The sandpile network features and the cascade behavior are analyzed. The results show that both the underlying urban forms and cascades show heavy-tailed scaling, the most prominent feature of complex systems. Statistical findings for both are comparable to those in previous works in the literature. Insights on the urban form and real-world cascades are also given. The cascade model is deemed a good starting point for analyzing the urban form and geographical flows, and illustrates the use of complex systems in addressing society\u27s problems in general