Testing the stability of a production function with urbanization as a shift factor

Urban economists have long sought to explain the relationship between urbanization levels and output. In this paper we revisit this question and test the long-run stability of a production function including urbanization using non-stationary panel data techniques. Our results show that a long-run relationship between urbanization, output per worker and capital per worker cannot be rejected for either our sample of 30 developing countries or our sample of 22 developed countries. We do find, however, that the sign and magnitude of the impact of urbanization varies considerably across the countries. In addition, we estimate the long-run average effects on GDPW of urbanization and capital. These results offer new insights and potential for dynamic urban models rather than the simple cross-section approach.