政策偏向、省会首位度与城市规模分布

2010年后,部分省份强化了提升省内中心城市首位度的政策导向,这种以行政手段提升首位度的做法,会对城镇格局以及居民福利产生怎样的影响?本文基于量化空间模型,将影响城市规模的因素分解为生产率、用地指标、用地结构、就业机会、外生舒适度与住房有效供给率等维度,利用反事实方法评估了提升首位度的相关政策对居民福利、GDP以及城市规模分布的影响。研究发现:①当省级层面给予省会及副省级城市更多用地指标时,可以在提高这些城市首位度的同时提升总体GDP水平,但会导致均衡时居民福利水平有所降低;②GDP与福利的非同步变动,源于户籍制度影响下人口要素与土地要素的空间错配,即省会及副省级城市人口集聚不足而一般地级市用地约束加强;③若降低落户门槛或消除省内城市间住房有效供给率的差异,均能使GDP与福利水平同时提高,且城市规模分布向Zipf定律收敛。为此,以提升经济密度为导向,以渐进的户籍改革为手段推动人口向省会及副省级城市集聚,多管齐下提高省会及副省级城市住房有效供给水平,是优化城市规模分布、实现新型城镇化高质量发展的关键。

Policy Bias,Primacy of Provincial Capital and City-size Distribution

Since 2010,some provinces have strengthened the policy orientation of improving the primacy of central cities within the province.How will this practice of promoting primacy through administrative means affect the urban pattern and residents’welfare?Based on a quantitative spatial model,this paper decomposes the determinants of city size into dimensions such as productivity,land quota,land structure,employment opportunities,exogenous amenities and effective housing supply rate,and uses the counterfactual method to evaluate the impact of policies to improve the primacy on residents’welfare,GDP and city-size distribution.The results show that:①When provincial capitals and sub-provincial cities were given more land quota,the overall GDP level could be increased while the primacy of these cities was increased,but the residents’welfare would be reduced.②The asynchronous change of GDP and welfare results from the spatial misallocation of population factors and land factors under the influence of hukou system,that is,the population concentration of provincial capitals and sub-provincial cities is insufficient and the land constraints of prefecture-level cities are strengthened.③If the threshold for settling down is lowered or the difference in the effective housing supply rate between cities within the province is eliminated,both GDP and welfare can be improved,and the city-size distribution converges to Zipf’s law.Therefore,it is key to optimize the city-size distribution and realize the high-quality development of new-type urbanization to promote the agglomeration of population to provincial capitals and sub-provincial cities by means of increasing economic density and gradual hukou registration reform,and to improve the effective housing supply rate of provincial capital and sub-provincial cities in a multi-pronged way.