The Empirical Research On The Optimum City Size In China

Since reform and opening up, the economy of our country acquired huge development, and the level of urbanization increased steadily, which had raised from 17.92% in 1978 to 43.9% in 2006. In the process that urbanization propels unceasingly, the contradictions that in city or between city and region were emerging increasingly, so the city size has become the focus that the academia, the government and the public attention, especially the academia .What is the most reasonable size of the city? How to determine the optimum city size? Cities of our country whether reaching the optimum city size? The research on these questions will be more important.On the basis of comparing predecessor's researches, this article chooses the 211 main cities as research samples, which including 30 provincial-level cities except for Lasa and 5 cities which planning individually and 176 prefectural metropolis in China, and collects the successive time-series data from the year 1989 to 2003 and 2000 to 2005, then sets up panel data models about the urban returns to scale and external cost, and using those models to estimate the urban returns to scale and external cost respectively, then concludes the optimum city size of our country through comparing the urban returns to scale and external cost. We conclude through the research: the optimum city size of our country is about 2.7 million persons, and meanwhile, the majority of prefectural metropolises have not reached the optimum city size yet.On reference to the theories of regional economics, urban economics, economics geography, agglomeration economics, this article has tried to estimate the optimum city size by using comparative analysis of the cost and the benefit, and hoping to give some reasonable suggestions for development of urbanization.This article is composed of three chapters apart from the preface and summary.Chapter one, summarize the optimum city size theory. The first part mainly introduces the theory advance and empirical research, generally from the aspects of agglomeration economies, agglomeration diseconomies and both the two to summarize.Chapter two, the methodology. The second part mainly introduces the returns to scale and measurement, the foundation of the urban returns to scale model, the urban external cost analysis and the confirmation of optimum city size.Chapter three. The third part firstly, introduces the index extraction and data origin, and explains the index simply; then, uses these indexes to inquire about the data and estimates the urban returns to scale, the urban external cost and the optimum city size respectively.