城市规模对绿色经济效率的影响及空间效应研究——基于我国285个地级及以上城市数据的实证分析

Study on the influence of city scale on the efficiency of green economy and its spatial effect:Empirical evidence from 285 prefecture-level and above cities in China

以2003—2018年中国285个地级及以上城市面板数据为样本,采用双固定效应空间杜宾模型,实证分析了城市规模对绿色经济效率的影响及空间效应。结果显示:城市规模、城市规模的平方以及绿色经济效率均具有正空间自相关性。城市规模对绿色经济效率的影响呈倒"U"型特征,目前中国绝大多数城市的人口规模位于倒"U"型曲线左侧。异质性分析发现,东部、中部和西部地区城市规模与绿色经济效率之间均呈倒"U"型关系,东部地区倒"U"型曲线顶点处的城市规模水平最高,中部次之,西部最低。空间效应分解表明,城市规模与相邻城市绿色经济效率之间也存在倒"U"型关系,并且在现阶段,城市规模对相邻城市绿色经济效率会产生正向空间溢出效应。

Based on the panel data of 285 cities at prefecture level and above in China from 2003 to 2018,this paper uses the double fixed effect spatial Durbin model to empirically analyze the impact of city size on the efficiency of green economy and its spatial effect.The results show that:city size,square of city size and green economic efficiency all have positive spatial autocorrelation;the impact of city size on green economic efficiency is inverted U-shaped;at present,the population size of most cities in China is on the left side of the inverted U-shaped curve;heterogeneity analysis shows that there is an inverted U-shaped relationship between city size and green economic efficiency in eastern,central and western regions The results show that the level of city size at the inflection point of the inverted U-shaped curve in the eastern region is the highest,followed by the central region,and the lowest in the western region;the decomposition of spatial effect shows that there is an inverted U-shaped relationship between city size and the green economic efficiency of adjacent cities,and at this stage,city size has a positive spatial spillover effect on the green economic efficiency of adjacent cities.