中文摘要：

本文运用新古典经济的框架建立了一个经济增长模型,系统分析了拥挤效应、经济增长与城市规模的关系。假设城市规模扩大产生集聚效应并反映为拥挤效应的降低,将拥挤效应作为影响经济增长的因素纳入生产函数,分析经济稳态的演化路径,得出最优的城市规模、合理的城市拥挤程度和稳定的经济增长速度,并分析扰动稳态的变量对演化路径的影响,据此给出了一个估算最优城市规模的简单模型的结论。研究表明在不同条件下城市的最优规模是可变的,不存在统一的最优城市规模,城市化进程应该适度有序的进行。

英文摘要：

In the framework of neoclassical economics,this paper established an economic growth model,and made a systematic analysis of the relationship between congestion effects,economic growth and city size. Through constructing a congestion effects function caused by expansion of city size,we showed that expansion of city size can generate agglomeration effect,which are reflected as a decrease of congestion effects,Meanwhile,congestion effects can affect economic growth by entering the production function,In addition,by analysis of the evolution path of steady-state economic,we solved for the optimal city size,a reasonable congestion degree and the stable economic growth rate,and then explored the evolution path affect imposed by the factors which may disturbance steady state. Finally,we gave a simple model to estimate the optimal city size. According to the analysis of this model,our paper showed that the optimal city size is variable under different conditions,and there is no unified optimal city size. Therefore,the process of urbanization should be moderate and orderly.