Urbanization, long-run growth, and the demographic transition

Advanced economies undergo three transitions during their development: (1) transition from a rural to an urban economy, (2) transition from low-income growth to high-income growth, (3) transition from high fertility and mortality rates to low modern levels. The timings of these transitions are correlated in the historical development of most advanced economies. I consider a nonlinear model of endogenous long-run economic and demographic change, in which child quantity-quality substitution is driven by declining child mortality. Because the model captures the interactions between all three transitions, it is able to explain three additional empirical patterns: a declining urban-rural wage gap, a declining rural-urban family size ratio, and most surprisingly, that early urbanization slows development. This third prediction distinguishes the model from other theories of long-run growth, and I document evidence for it in cross-country data.