Using Crowdsourced Data to Assess the Impact of Shelter-in-Place Orders (SIPO) during COVID-19: Lessons from a Small Island Developing State

Without the availability of a vaccine (at the time of writing) to control the spread of the COVID-19 virus, countries must rely largely on lockdown measures to limit population movement and community spread. The case of COVID-19 in small island territories is particularly important given their vulnerabilities to external shocks, limited capacity to prepare for and respond to a health crisis, and a population susceptible to non-communicable diseases. This article utilise novel crowdsourced cell phone data gathered by Facebook Data for Good and difference-in-differences estimation as well as event studies to examine the effectiveness of shelter-in-place orders (SIPOs) on population movement patterns across Trinidad and Tobago. We find that most SIPOs result in reductions in population movement patterns across the country, the most effective being the closure of all public places and non-essential businesses. Also, the relaxation of these measures does not readily result in increasing population movement patterns, indicating relative embeddedness in population movement. Our results further suggest that voluntary compliance, adaptive behaviour among citizens, government transparency and public information can also be important motivations for reduced population movement during the pandemic.