The Ohio Vaccine Lottery and Starting Vaccination Rates

Abstract

We find that Ohio's "Vax-a-Million" lottery increased Covid-19 vaccinations by between 50,000 and 80,000 doses in the first two weeks. We use county-level data and two empirical approaches to provide causal estimates of the lottery in Ohio. First, we use a difference-in-differences design, comparing vaccination rates in border counties in Ohio and Indiana before and after the announcement. Second, we use a pooled synthetic control method to construct a counterfactual for each of Ohio's counties using control counties in Indiana, Michigan, and Pennsylvania. The synthetic control analysis reveals larger increases in vaccination rates in more populous counties. At a cost of $5,600,000, our estimates imply that the lottery increased vaccinations for about $85 per starting dose during this period.