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.

中文翻译：

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城市化、长期增长和人口转变

发达经济体在发展过程中经历了三个转型：（1）从农村经济向城市经济转型；（2）从低收入增长向高收入增长转型；（3）从高生育率和死亡率向低现代水平转型. 这些转变的时间与大多数发达经济体的历史发展相关。我考虑了一个内生的长期经济和人口变化的非线性模型，其中儿童数量质量替代是由儿童死亡率下降驱动的。由于该模型捕捉到了所有三种转变之间的相互作用，因此它能够解释另外三种经验模式：城乡工资差距缩小、城乡家庭规模比例下降，以及最令人惊讶的是，早期城市化减缓了发展。