Product Quality and Market Size*

Do larger markets offer better products? The question has implications for theories of cities and theories of market organization. We document that in the restaurant industry, where quality is produced largely with variable costs, the range of qualities on offer increases in market size. In daily newspapers, where quality is produced with fixed costs, the average quality of products increases with market size, but the market does not offer much additional variety as it grows large. These results are consistent with IO theories of endogenous product quality and with theories that emphasize the consumption advantages of cities.