【作者】 李金滟；

【导师】 宋德勇；

【作者基本信息】 华中科技大学 ， 西方经济学， 2008， 博士

【摘要】 为了考察城市产生和演化背后的原因和机制,本文构建了一个新经济地理分析框架,对城市集聚进行理论研究,并以中国数据作为经验支撑。其中综合运用了区位和社会空间辩证分析方法,并结合了数理建模和计量经济学分析手段。从本文的视角来看,城市是人口和经济活动集聚的某个空间范围,城市的产生和发展源于不同的外部性所产生的集聚效应,当集聚力起主导作用时,集聚收益大于集聚成本,产生集聚经济,城市处于成长期;当分散力起主导作用时,集聚成本大于集聚收益,产生集聚不经济,城市会通过向外扩张以分摊成本,如果集聚成本快速上升,超过了一定的极限,城市将会进入衰退期。在整个区域层面,城市集聚既是区域非均衡发展的产物也是其原因。因此,本文首先是综合城市模型和中心—外围模型基本特征,建立新经济地理数理模型,为城市集聚中依次出现的城镇、城市极和城市群,提供了一个一般性解释。然后,利用模型,考察了1978年后中国地区差距、城市形态、经济结构和劳动力流动的阶段性特征之间的内在联系。该模型还表明,正是集聚过程中向心力和离心力间的此消彼长,才决定了城市集聚的空间形态和经济效应。在单个城市层面,本文分别从集聚经济和集聚不经济两方面展开研究。集聚经济既包括静态集聚经济,也包括动态集聚经济。静态集聚经济,主要研究外部性来源和作用机制,从而为城市产生原因和类型差异提供解释。对于城市集聚中出现的明显的专业化和多样化差异,本部分首先通过对资金外部性和技术外部性的细分,并加入交流外部性来区分了其不同的外部性来源;其次,又对其集聚机制分别从中间品投入、公共品和市场区进行了研究,并从资金联系和技术联系上分析了不同类型城市并存的原因;再次,具体针对中国284个地级市,实际测算了其专业化和多样化指数,考察了这些城市在空间和时间上的专业化和多样化特征差异;最后,利用2003—2005年面板数据,分析和比较了影响城市集聚经济的因素,其中特别考察了专业化和多样化的相对贡献。动态集聚经济,是研究城市集聚产生后,什么样的因素和机制可以推动城市的经济增长。本部分首先对城市化、城市集聚和经济增长之间的理论联系进行了考察,从而减少了经验分析中关于内生性的争论;其次,在对城市集聚促进经济增长的机制的考察中,除了市场机制,本部分还增加了对非市场机制和空间组织系统的研究;最后在对中国的经验研究中,本部分以劳动生产率和就业密度分别作经济增长和城市集聚的代理变量,利用1998—2005年中国209个地级市面板数据,考察了就单个城市而言,促进其经济增长的主要因素,其中特别是城市集聚的影响。单个城市的集聚不经济源于集聚成本的快速上升。本文也正是基于对集聚成本的研究,提出了制定相关政策的新视角。在促进城市集聚的向心力中,无论是市场的还是非市场的因素,都具有很强的自我强化特性,这意味着在市场经济条件下,各地方政府单纯促进集聚收益的政策是相对有限的。然而,考虑到城市集聚经济是收益减去成本后的净效应,并且微观经济主体往往是“自利”而非“自制”的,那么地方政府的城市政策重点就应该放在集聚成本的控制上。因此本文对三类主要的城市集聚成本——土地成本、环境成本和社会成本,分别进行了理论和经验上的研究,其中特别对城市污染与收入水平、城市污染与人口规模作了较为详尽的面板数据计量分析;与集聚成本相对应,提出了城市治理中的三条准则——土地利用规划中的理性增长、环境资源管理中的可持续发展和社会关系调整中的和谐共融。更多还原

【Abstract】 With an effort to examine the causes and mechanisms behind the urban emergence and evolution, the paper constructs a new economic geography framework to study the urban agglomeration theory supporting with a lot of evidence from China, under which location and socio-spatial dialectic are adopted and the methodology combining mathematical models with empirical analysis is included. In the perspective of this paper, city is certain spatial space where people and economic activities agglomerating and its emergence and evolution may result from agglomeration effects of different externalities. When agglomeration forces dominate, agglomeration economies emerge because agglomeration returns exceed costs, and the city is in its development. While the dispersion forces dominate, agglomeration diseconomies emerge and the city will expand its geography scope to decrease agglomeration costs. The fast growth of agglomeration costs and its exceeding of certain limits will cause the city recession.From a whole region perspective, urban agglomeration may result from meanwhile result in regional unbalanced development. With the basis of new economic geography framework, the paper presents a mathematical model featuring of Thünen-Alonso model and core-periphery model, which provides a general explanation for the successive emergence of town, urban pole and megalopolis in urban agglomeration. Then the model is used to explain the internal relations in periods of regional disparity, urban configuration, economic structure and labor migration in China since 1978. There is also an indication in the model that it is the tension between centripetal forces and centrifugal forces that decides the urban spatial configuration and economic outcome.From a single city aspect, the paper examines both agglomeration ecnomies and diseconomies. Agglomeration economies include static and dynamic economies.Static agglomeration economies focus mainly on the sources and mechanisms of externalities that can be used to explain the emergence of cities and their different types. For the obvious differences of specialized and diversified cities in urban agglomeration, this part firstly explains different sources for urban agglomeration externalities by subdividing and extending pecuniary externality, technology externality and communication externality. Also in this part the agglomeration mechanisms including intermediate input, public goods and market place are examined and the reason for the specialized and diversified city co-existing is interpreted with different pecuniary and technology links. Then, in accordance with the situation in China,the specialization and diversification indexes for Chinese prefecture-level cities are calculated to analyze the differences of cities in different time and space. Using a panel data of 284 prefectures in China from 2003 to 2005, this part examines the factors affecting urban agglomeration economies and in which especially compares the relative contributions of specialization and diversification.The study of dynamic agglomeration economies focuses on what factors and mechanisms will hasten the economic growth of cities after their emergence. This part begins with the examination on the theoretical relations of urbanization, urban agglomeration and economic growth thus the less argument on the endogeneity in empirical analysis. In the study on the mechanisms, not only market mechanism but also non-market mechanism and spatial organization system are included. Finally, in the empirical analysis on China, the paper chooses productivity and employment density as agent varibles, with panel data composed of 209 prefectures from 1998 to 2005, to examine the factors promoting economy of a single city, especially the influence of urban agglomeration.Agglomeration diseconomies of a single city originate from the fast growth of agglomeration costs. With the basis of the study on agglomeration costs, the paper poses a new perspective for related polciy formulation. Those centripetal forces, no matter from market or non-market factors, all strongly show self-reinforcing features, which means the local government’s policies on pure promotion of agglomeration returns are relatively limited under market economy environment. However if we take it into our consideration that urban agglomeration economies are net effects in which costs are excluded from returns, and economic agents are usually selfish but not self-restrained, local governments should strengthen the control of agglomeration costs. Therefore this paper investigates theories and experiences respectively of three types of main agglomeration: land costs, environment costs and social costs, and especially provides detailed panel data analysis of the relations between pollution and income level, pollution and population size. Correspondingly, the paper proposes three principles for city governance: smart growth arises in land use planning, sustainable development in environmental resources management and harmony in social relations adjustment.更多还原