Geography and Economic Transition: Global Spatial Analysis at the Grid Cell Level

This paper addresses the timing of historical transition from rural to urban activity. In our model, rural production has constant returns and meets subsistence needs, while urban production has scale economies and meets the demands of higher-income consumers. Urbanization occurs sooner when rural or urban productivity is higher or transport costs are lower. We test the model on worldwide data that divides the earth's surface at half-degree intervals into over 60,000 cells. From an independent estimate of each cell's rural and urban population history, we identify the date at which each cell achieves various thresholds of urbanization. Controlling for country fixed effects and neighbors' urbanization using spatial techniques, we find that the date at which each cell passes each urbanization threshold is positively associated with its suitability for cultivation, having seasonal frosts, more access to navigable waterways and lower elevation. Aggregating cells into countries, an earlier urbanization date is linked to higher per capita income today.