Descoberta de relações alométricas entre população e crime dentro de uma grande metrópole

Abstract

Recently humanity has just crossed an important landmark in its history with the majority of people now living in large cities. This population concentration is capable of boosting the growth of positive indicators such as innovation, the production of new patents and supercreative employment, but increases the spread of diseases and the occurrence of crimes. Faced with the realization that crime rates grow year after year in these large urban centers, we sought to understand the dynamics of crime within cities. We investigate at the subscale of the neighborhoods of a highly populated city the incidence of property crimes in terms of both the resident and the floating population. Our results show that a relevant allometric relation could only be observed between property crimes and floating population. More precisely, the evidence of a superlinear behavior indicates that a disproportional number of property crimes occurs in regions where an increased flow of people takes place in the city. For comparison, we also found that the number of crimes of peace disturbance only correlates well, and in a superlinear fashion too, with the resident population. Our study raises the interesting possibility that the superlinearity observed in previous studies [Bettencourt et al., Proc. Natl. Acad. Sci. USA 104, 7301 (2007) and Melo et al., Sci. Rep. 4, 6239 (2014)] for homicides versus population at the city scale could have its origin in the fact that the floating population, and not the resident one, should be taken as the relevant variable determining the intrinsic microdynamical behavior of the system. This finding was the motivation for the codification of a framework that supports the analysis of population and crime data to propose city divisions that allow the allocation of police by floating population and resident population statistics.