Does urbanization cause crime? Evidence from rural–urban migration in South Africa
利用2011-2018年南非市级面板数据，研究发现由气候冲击驱动的农村-城市迁移导致城市人口密度增加，反而降低了财产犯罪率，但对非财产犯罪率无显著影响，机制在于人口构成变化和社会网络效应。
We study the impact of urbanization driven by internal migration on crime in South Africa. We create a new dataset that combines yearly data on crime and urban population density at the municipality level from 2011 to 2018. We exploit exogenous variations in rural–urban migration induced by climate shocks at origin for identification. We show that higher urban population density leads to a reduction in pecuniary crime rate but has no effect on non-pecuniary crime rate. This negative effect operates through changes in population composition and a social network effect.