Выбор редакции

Impacts of State Reopening Policy on Human Mobility -- by Thuy D. Nguyen, Sumedha Gupta, Martin Andersen, Ana Bento, Kosali I. Simon, Coady Wing

We study the effect of state reopening policies on multiple measures of human mobility and interaction during the COVID-19 epidemic. We document the timing and gradualness of the reopening plans that are occurring in different states, and we use data on multiple measures based on cell device signals to assess behavior during the reopening phase. Our empirical analysis suggests four main results. First, we document that after a substantial decline during the lock down period, there as been a clear increase in mobility levels in most states since mid-April. The resurgence of mobility is small relative to the decline since mid-March, but it is observable across a broad range of different cell device based metrics. Second, the size of the increase in mobility across counties is strongly associated with temperature and precipitation patterns. Third, event study analysis finds that by four days after reopening, the causal effect of policy on most measures of mobility is an increase of about 4% to 8%. Demonstrating the importance of using multiple measures of human mobility, the full range of point estimates spans 1% to 22%, without substantial pre-trend concerns. For example, there are larger effects on the variety of venues people visit than on the fraction leaving their homes. Fourth, the largest increase in mobility from reopening seems to occur in states that were late adopters of closure measures, suggesting that closure policies may have represented more of a binding constraint in those states.