题目：“经济学系列讲座”第42期 The Effect of Driving Restrictions on Mobility: Evidence from China
Driving restrictions keep motor vehicles off the road on the basis of the last digit of the license plate number. This paper studies the impact of driving restrictions on intra-city and inter-city mobility in four Chinese provinces. I exploit the variation in policy adoption dates and end dates across cities, and employ a two-way fixed effects estimator. Using city-level aggregate data from a mapping app, I find that, before COVID-19, driving restrictions had no effect on intra-city mobility overall, but more people traveled on days when fewer vehicles were restricted. Furthermore, driving restrictions increased the fraction of trips undertaken for work purposes. On inter-city mobility, I find that, before COVID-19, driving restrictions reduced both in-migration and out-migration.