Estimating the Impact of Attendance at MLB Games on Air Pollution

Abstract

PLACES Student Paper Award Winner (2023) (long paper winner). Baseball games draw tens of thousands of fans to a single stadium on game days. These individuals have different means of getting to the venue, but one of the most popular methods is using personal vehicles. These vehicles are known to produce many pollutants, including nitrogen oxides and certain volatile organic compounds that create ozone if they react in the air. This paper studies the impacts of Major League Baseball attendances on ozone Air Quality Index values between 2010 and 2019 in 27 American cities that host MLB teams. I follow Locke (2019), who found a statistically significant but negligible link between MLB attendance and ozone. I assess the robustness of this result by including three additional years’ worth of data as well as control variables for attendances at NBA and NHL games occurring in the same city, which could account for some of the additional ozone observed. The study finds that MLB game attendances have a significant but small impact on local ozone air quality values, with each additional thousand fans leading to an increase in ozone AQI of 0.013.