谁从贸易中获益更大:大城市还是小城市?

Which Gains More from Trade Openness: Big or Small Cities?

学界对国际贸易与劳动力市场之间关系的研究保持浓厚兴趣。中国幅员辽阔,各地区的贸易条件和贸易政策存在较大差异,由此各地区劳动力市场从贸易开放中的获益也不相同。构建一个劳动力流动受限的城市经济模型并分析其均衡结果,可从理论上探讨了贸易开放度冲击对一国内部不同规模城市的劳动力市场的异质性影响。理论分析表明,贸易开放度的提高能够提高城市的就业规模和劳动力工资水平,但这种作用在不同规模的城市存在异质性,贸易开放对就业规模的影响在小城市要大于大城市,对劳动力工资的影响在大城市要大于小城市。基于1999—2007年中国城市面板数据,估算中国不同城市所面临的贸易政策不确定性程度;然后以中国加入WTO后美国授予中国的"永久性正常贸易伙伴关系"为准自然实验,构建双重差分模型和三重差分模型,从贸易不确定下降这一视角实证检验了贸易开放度的提高对城市劳动力市场的影响及其异质性特征。实证研究表明,理论分析结果在中国城市层面是成立的。

This paper theoretically explores the heterogenous impact of trade openness on the labor markets in cities of different sizes within a country. By constructing an economic model with limited labor mobility and analyzing its equilibrium results, the theoretical analysis shows that the increase of trade openness can raise cities’ employment scale and labor wage levels, but these effects are heterogeneous in cities of different sizes. The impact of trade openness on employment scale is greater in small cities than in large cities, whereas the impact of labor wages is greater in large cities than in small cities. We used the Permanent Normal Trade Partnership granted to China by the U.S. following China’s accession to the WTO as a quasi-natural experiment, and utilized the 1999-2007 Chinese city panel data. Estimating the degree of trade policy uncertainty faced by different cities in China and constructing a DID model and a DDD model, this paper empirically tests the impact of increased trade openness on the urban labor market and its heterogeneity from the perspective of the decline of trade policy uncertainty. Empirical research demonstrates that the theoretical analysis results of this paper are valid at the Chinese city level.