Externalities, Indivisibility, Nonreplicability, and Agglomeration

In this paper we argue that the impact of external scale economies and diseconomies on city size is not nearly as clear-cut as it is tacitly believed in urban economics. Similarly, city-size distortions are not caused by externalities alone. Indivisibility and nonreplicability, which prevent establishing the “right” number of cities, may represent a source for city-size distortions which can be stronger than the standard resource misallocation resulting from external scale economies and diseconomies. It follows that a direct population dispersion policy is not just an inferior substitute to Pigouvian taxes and subsidies but rather a useful complement.     

“流”视角的长春市蔓延特征与作用机理分析

各种"流"是城市内在空间结构组织的微观主体,为城市蔓延特征及其作用机理的分析提供了一个更为动态、微观和系统的分析视角。据此,基于"流"视角,以长春市为例,运用弹性系数测度其蔓延程度,用紧凑度、破碎度和轴带扩展度分析其蔓延扩展方式,并从产业、空间结构、体制环境和地理区位的演变等方面透视了"流"之于长春市蔓延的作用机理。最后从政府绩效考核体系、征地制度、分税制、财政转移支付等视角提出对策措施。     

Dynamics of urban sprawl and sustainable development in China

Compared with the rich literature on urban sprawl in Western cities, relatively little is known of the driving factors, processes, and future trends of urban sprawl in China. This research analyzes the socioeconomic forces behind two parts of urban sprawl in China: urban decentralization and urban renewal, and reveals two basic characteristics of Chinese urban sprawl: de-densification and expansion of urbanized areas. It uses the term “urban sprawl” to consider the reasons behind urban transformation on a regional level in China. This research begins with definitions of sprawl in Western and Eastern countries, and follows with a dynamic analysis of the social, political, and cultural aspects of sprawl. Three case studies focus on three urban regions in China: Beijing, Shanghai, and Guangzhou. This research provides a comprehensive definition of “urban sprawl” in China, identifies the patterns of urban sprawl and growth, and indicates possible alternative strategies for urban expansion. Finally, it offers suggestions on how to effectively control urban sprawl in China, and provides a pathway to achieving sustainable development.     

The effects of transportation system improvements on urban performances with heterogeneous residents

Through developing a spatial equilibrium model for a linear monocentric city with a bi-modal traffic corridor (i.e., highway and public transit), this paper examines the effects of transportation improvements (including the decreases of the fixed travel cost, the travel time and monetary cost per unit distance) on urban spatial structure and the utilities of the two resident classes, namely car-available-residents (CARs) and car-unavailable-residents (CURs). As a result, it is demonstrated that the city size increases with the improvements of vehicle-highway system and the degree of CARs’ travel mode choice rationality, but the improvement of public transit may produce a shrinkage rather than an expansion in city size. From the aspect of utility, both CARs and CURs benefit from the improvement of vehicle-highway system; however, the improvement of public transit might have an adverse effect on the utility of CARs. These findings would provide valuable reference for the future transportation and urban planning.     

从"城市蔓延"到"理性增长"——美国土地利用方式之转变

从美国郊区化与城市蔓延的典型特征入手,简要回顾了理性增长产生的背景.在此基础上,从内城贫困、居住隔离、空间失衡和公正健康四个层面分析了城市蔓延引发的社会及经济后果.随后就若干论点介绍了城市蔓延与理性增长之间的理论之争.最后借鉴美国经验教训,对我国城市化道路和土地利用模式展开思考,认为要转变方式,树立科学的区域发展观;借鉴西方城市健康的分析框架,努力探索"健康城市规划";充分发挥规划政策在应对城市土地利用问题的综合调控作用;公平公正,追求社会稳定和谐,发挥政府力量对市场扭曲的矫正作用.     

Class diversification,economic growth and urban sprawl: evidences from a pre-crisis European city

Economic expansion indirectly promotes class diversification at the neighbourhood scale with a consequent reduction of social divides at the regional scale. To verify this working hypothesis, the present study investigates class diversification at both spatial scales in a Mediterranean city (Athens, Greece) using the European Socioeconomic Classification based on population census data referring to 1991–2001, a phase of economic expansion and intense urban sprawl preceding the 2004 Olympic games. Results of multivariate analysis and diversity indexes outline a local-scale social mix associated to suburban expansion, and regional-scale class segregation, reflecting an increasing polarization in affluent and economically deprived urban districts. The contrasting pattern at the two spatial scales results in a complex social geography with class diversification and moderate changes over time in the economic spatial divide between urban and neighbouring rural areas. These findings contribute to design scale-dependent policies reducing social inequalities and improving quality of life in urban areas. Future paths for socio-spatial processes were delineated for sprawling metropolitan regions under economic expansion and discussed in the light of future demographic trends in both developed and emerging countries.     

Income taxes and urban spatial structure

This paper examines the impact of an income tax in a monocentric city where households equilibriate their allocation of time between work, commuting, and leisure. An increase in the income tax rate lowers the implicit value of time, and hence transportation costs. “Compensated equilibrium” comparative statics analysis shows that under certain conditions, this results in a larger, more dispersed urban area, with lower land rents at the city center and less population within any given distance from the center. The welfare effect of an income tax rate change is also studied, and an expression for the marginal excess burden is derived. The income tax produces welfare losses both because it induces substitution in favor of leisure and in favor of travel—the latter accompanied by excessive spatial dispersion and consumption of space. The marginal excess burden depends not only on the compensated demand elasticity for leisure, but also on that for space. Finally, the problem of benefit measurement for transportation projects in this tax-distorted spatial economy is examined. Benefit measures should be deflated to adjust for the fact that further transportation improvements lead to reduction of land use intensity, exacerbating the problem of spatial resource misallocation in an already excessively dispersed urban area.     

住房自有率与城市蔓延：理论与实证

通过构建一个包含住房租赁市场的封闭、单中心城市一般均衡模型，模型化了住房自有率与城市蔓延之间的关系，理论模型结论显示：首先，与自有住房者相比，租房者倾向于居住在离市中心较近的地方；其次，住房自有率的提高会使城市空间面积扩大，加剧城市蔓延。进一步，利用地级市数据分别对理论命题结论进行了检验，在比较充分地控制内生性问题后，实证结果证实了高住房自有率会加剧城市蔓延。因此，长期以来我国不断升高的住房自有率也是加剧我国城市蔓延的重要原因。     

Spatial interactions among U.S. cities: 1900–1990

We test implications of economic geography by exploring spatial interactions among U.S. cities. We use a data set consisting of 1900–1990 metro area populations, and spatial measures including distance from the nearest larger city in a higher-tier, adjacency, and location within U.S. regions. We also date cities from their time of settlement. We find that among cities which enter the system, larger cities are more likely to locate near other cities. Moreover, older cities are more likely to have neighbors. Distance from the nearest higher-tier city is not always a significant determinant of size and growth. We find no evidence of persistent non-linear effects on urban growth of either size or distance, although distance is important for city size for some years.     

大城市边缘区演化发展中的矛盾及对策——基于广州市案例的探讨

在辨析边缘区概念发展的基础上,指出边缘区已成为大城市发展的核心空间,实质上承担了大都市"自上而下"的空间外拓和撤市(县)设区后"自下而上"式的城镇蔓延.通过分析大城市边缘区的演化,归纳了演化要素、结构模式、管理方式、空间边界等若干要素和特征,并提出对"边缘区"内涵的补充.由此展开对广州市案例的研究,从空间形态、产业发展、土地利用、规划管理多方面分析二元发展的矛盾及深层原因,并进一步探索新发展背景下大城市边缘区治理体系建构的合理模式.     

Income class, modal choice, and urban spatial structure

This paper analyzes the impacts of urban transportation system changes and income changes on the welfare of people and on the urban spatial structure, in a setting where the income level differs between two groups, and two transportation modes compete with each other in a city. It is demonstrated that an improvement in some transport facility will not necessarily increase the welfare level of every household, and, at times decreases the welfare of some households. It also is argued that under particular situations, an improvement in a particular transport mode may produce a contraction in the city size rather than an expansion. Similarly, an increase in income of one group might have an adverse effect on the welfare of another income group as a result of competition in the land market.     

新城市主义及精明增长之解读

二战后,美国城市向郊区的无序蔓延带来了许多负面影响,针对"城市蔓延"问题,"新城市主义"和"精明增长"理论应运而生.首先,深入解读了"新城市主义"及"精明增长"的思想内涵,其次,总结了二者在核心内容上的理论共识以及侧重方向,最后,基于美国与中国城市发展的背景差异,对"新城市主义"和"精明增长"的中国化问题做了探讨.     

Do inter-city differences in intra-city wage differentials have any interesting implications?

Recent research has related characteristics of cities to differences in the distribution of wages across workers with different skill levels. We demonstrate that these differences in wage differentials arise naturally as a compensating variation in Rosen’s theoretical model of inter-city wages. For example, if the income elasticity of demand for housing services is less than unity, cities with higher house prices will have smaller money wage differentials between low and high skill workers. This result has no implications for differences in either absolute or relative real productivity or welfare of unskilled workers. Similarly, changes in the amenity of an urban area may result in changes in relative wages of skilled and unskilled workers with no implications for real productivity or welfare differentials.Empirical tests in which housing cost differentials are added as a determinant of inter-city differences in an intra-urban wage differential model provide empirical confirmation of the theoretical expectations. It appears that intra-urban money wage differentials, differences in the quality of life, and variation in the cost of living in each city are jointly determined variables just as Rosen’s model of inter-city wage differentials predicts.     

转型期中国城市土地空间扩张问题研究——基于Muth-Mill模型的实证检验

论文分析了经济转型背景下市场化改革和政府制度转型如何影响中国城市的空间扩张过程,并基于1998年、2002年、2004年和2006年中国地级市建成区数据对Muth-Mill模型进行实证检验.结果表明经济增长、人口城市化、交通改善、服务业发展是中国城市空间规模扩张的主要原因;分年度的回归表明,近年工业化对城市空间规模的影响不显著;受国家对土地空间规制的影响,城市对农村的相对效用未能影响城市的空间变化.     

长三角城市群空间扩张的模式、类型与效益

通过对长江三角洲地区城市群近年扩张动态进行研究,可以明确经济发达区域在城市扩张过程中存在的问题。采用夜间灯光数据(DMSP/OLS)提取长三角城市群空间信息,分析城市群扩张模式,基于灯光数据构建复合指标,划分城市群扩张类型;在此基础上,选择典型城市进行扩张效益评价并进行了耦合分析。     

Political economy of commuting subsidies

We study the political economy of commuting subsidies in a model of a monocentric city with two income classes. Depending on housing demand and transport costs, either the rich or the poor live in the central city and the other group in the suburbs. Commuting subsidies increase the net income of those with long commutes or high transport costs. They also affect land rents and therefore the income of landowners. The paper studies how the locational pattern of the two income classes and the incidence of landownership affects the support for commuting subsidies.     

The Rank-Size rule in the absence of growth

This paper makes a discovery in comparing Steindl's model of a growing system of cities to Champernowne's model of a stationary one: While the so-called Pareto coefficient (a measure of size concentration) of the city size distribution for a growing system is determined by the ratio of the average rate of growth in the sizes of cities to the rate of growth in the number of cities, and is thus independent of the variance in growth rates across cities, and also, to a large degree, independent of their behavior over time, the coefficient is directly proportional to this variance in the case of stationarity. This has interesting policy implications: As long as the urban system is growing as a whole, efforts to reduce rates of growth in high-growth areas and to raise them in low-growth areas, i.e., to reduce the dispersion in growth rates across cities, will have no effect on the shape of the size distribution of cities. However, if the system were to cease to grow, these same efforts would have a potentially great effect on this distribution. This suggests that the customary pessimism expressed by students of urban phenomena in the efficacy of legislation to alter the form of the size distribution of cities, a pessimism induced by their observation of the persistence of the current distribution over time in many countries, is primarily due to the circumstances in which these systems are observed, i.e., in periods of growth and expansion.     

The holdout problem, urban sprawl, and eminent domain

Developers attempting land assembly often face a potential holdout problem that raises the cost of development. To minimize this extra cost, developers will prefer land whose ownership is less dispersed. This creates a bias toward development at the urban fringe where average lot sizes are larger, resulting in urban sprawl. This paper examines the link between the holdout problem and urban sprawl and discusses possible remedies, including the use of eminent domain for urban redevelopment.     

城市边缘区大型公共设施的规划

本文从大型公共设施在边缘区发展的影响因素入手 ,借鉴、分析国外的经验和教训 ,研究大型公共设施的建设与城市演变的关系 ,提出大型公共设施的建设应从城市发展战略、城市交通体系与政策、城市经济与环境以及城市建筑设计等多角度进行综合一体化规划设计 ,并以此促进城市重要建设项目的规划选址、规模布局、建筑计划等工作程序进一步规范和完善     

Equivalence of central place and economic base theories of urban growth

Economic base theory is discredited as a theory of urban growth; central place theory, although receiving some criticism, continues to enjoy some acclaim. In this paper I show that these two theories are equivalent so that previous criticisms of base theory also apply to central place theory. None-theless, the market expansion in both theories can lead to productivity increases because “the division of labor is limited by the extent of the market.”