How Dark Is Dark? Bright Lights, Big City, Racial Profiling
改进了Grogger和Ridgeway利用夏令时切换检验警察种族定性的方法，通过加入纽约州锡拉丘兹的路灯位置数据，发现白天黑人司机被拦停的几率比黑暗时高15%。
Abstract Grogger and Ridgeway (2006) use the daylight saving time shift to develop a police racial profiling test that is based on differences in driver race visibility and (hence) the race distribution of traffic stops across daylight and darkness. However, urban environments may be well lit at night, eroding the power of their test. We refine their test using streetlight location data in Syracuse, New York, and the results change in the direction of finding profiling of black drivers. Our preferred specification suggests that the odds of a black driver being stopped (relative to nonblack drivers) increase 15% in daylight compared to darkness.