Bigger Is Better: Market Size, Demand Elasticity, and Innovation*

This article proposes a novel mechanism whereby larger markets increase competition and facilitate process innovation. Larger markets, in the sense of more people or more open trade, support a larger variety of goods, resulting in a more crowded product space. This raises the price elasticity of demand and lowers markups. Firms, therefore, become larger to break even. This facilitates process innovation, as larger firms can amortize R&D costs over more goods. We demonstrate this mechanism in a standard model of process and product innovation. In doing so, we question some important results in the new trade and endogenous growth literatures.