Convergence in per capita income turns on whether technological knowledge spillovers are global or local. Global spillovers favor convergence, while a geographically limited scope of knowledge diffusion can lead to regional clusters of countries with persistently different levels of income per...

In this paper, I analyze recent findings by Coe and Helpman (1995) on trade-related international R&D spillovers. A Monte Carlo based robustness test is proposed which compares the elasticity of domestic productivity with respect to foreign R&D estimated by Coe and Helpman with an elasticity...