城镇化、外部性与生育水平

Urbanization,Externality and Fertility

针对快速城镇化过程中生育水平下降的典型事实,提出生育行为的正外部性作用机制,扩充Sato和Yamamoto(2005)的理论模型解释上述现象,采用面板模型求证理论推断。实证结果显示:全国层面上,城镇化的推进会轻微降低生育,但不显著;城镇化率低于50%的区域,城镇化的推进会显著地降低生育;城镇化水平高于50%的区域,城镇化的推进至少不降低生育,甚至还会促进生育,即城镇化与生育水平之间可能存在U型关系。进一步采用代理变量二三产业产值占比和人均产出进行敏感性分析,结论依然稳健。本文的理论意义和政策启示在于,人们在关注城镇化对生育行为转变所发生的作用时,将会注意到生育行为的正外部性;未来控制生育水平下降的重点应放在城镇化水平较低、经济欠发达的中西部地区。

Based on the typical fact that the fertility level fallsin the process of fast - speed urbanization,we propose a positive external mechanism of fertility behavior, use the theoretical model of Sato and Yamamoto （2005） to explain the above phenomenon, using Panel model to testifytheoretical inference. On the national level, promoting urbanization slight crowd out fertility, but not significant;for the area that urbanization rate is less than 50%, urbanization will significantly reduce fertility ,for the area that urbanization rate is more than 50%, urbanization at least not lower fertility, even promote fertility, there is a U type relationship between urbanization and fertility level, using proxy variables to do the sensitivity analysis , the result is still robust. The theoretical significance of this paper is to make people pay attention to the positive externalities of fertility behavior in the process of industrialization, the policy implication is that the future work focus of control decline in the level of birth should be placed on the relatively low level of urbanization, the underdeveloped central and western regions.