Simulation of urban perforation after random vacant plot generation: application of the thinning point process

Abstract

The spatial patterns of the generation and accumulation of vacant plots tend to be randomly distributed. This phenomenon, which represents morphological changes in urban areas, is called urban perforation. Urban perforation should be considered when discussing the spatial compaction of existing morphological urban areas; therefore, the morphological changes in urban areas caused by urban perforation must be simulated. However, suitable simulation methods have not been developed. This study applied the thinning point process developed in stochastic geometry to simulate the generation and accumulation of vacant plots and answered the following research questions based on empirical analysis in Sakura, Japan: (1) Can the thinning point process be used to simulate spatially random patterns of vacant plot generation in each built cluster? (2) Will accumulated vacant plots exhibit spatially random patterns in each built cluster after repeating the thinning point process? Evaluations of simulation performance revealed that the thinning point process did not always produce spatially random patterns of vacant plot generation and accumulation; however, the simulated dispersed patterns were logically consistent with urban perforation and revealed fragmented vacant plots. The results of this study may be used to predict future morphological urban areas in an era of urban shrinkage.