An Empirical Analysis of the Daily Labor Supply of Stadium Vendors

This paper analyzes the daily labor supply behavior of food and beverage vendors at a single stadium over an entire baseball season. This labor market is attractive for the study of labor supply both because the vendors unilaterally decide whether to participate on each game date and because changes in product demand conditions across days are large and highly predictable, generating exogenous game-to-game variation in the vendor "wage." I exploit the observable shifts in product demand conditions across games to estimate the labor supply (participation) elasticity of stadium vendors. Estimates that recognize that demand conditions and vendor labor supply decisions simultaneously determine the vendor wage always find substantial labor supply elasticities, typically in the .55-.65 range. In contrast, estimates that ignore the endogeneity of the vendor wage yield severely downward-biased labor supply elasticities. These results highlight the importance of using demand shift instruments to identify labor supply elasticities in specific labor markets