A Spatial Explanation for the Balassa-Samuelson Effect

Péter Karádi and Miklós Koren

October 2008

Abstract

We propose a simple spatial model to explain why the price level is higher in rich countries. There are two sectors: manufacturing, which is freely tradable, and non-tradable services, which have to locate near customers in big cities. As countries develop, total factor productivity increases simultaneously in both sectors. However, because services compete with the population for scarce land, labor productivity will grow slower in services than in manufacturing. Services become more expensive, and the aggregate price level becomes higher. The model hence provides a theoretical foundation for the Balassa--Samuelson assumption that productivity growth is slower in the non-tradable sector than in the tradable sector. Empirical results confirm two key implications of the theory. First, we compare countries where land is scarce (densely populated, highly urban countries) to rural countries. The Balassa--Samuelson effect is stronger among urban countries. Second, we compare sectors that locate at different distance to consumers. The Balassa--Samuelson effect is stronger within sectors that locate closer to consumers.