邯郸地区城镇规模体系的演变

使用首位度指数、位序——规模律及基尼系数的方法对邯郸地区1996、2001、2004、2006年四个年份的城镇规模分布的演变进行了分析,结果显示邯郸地区首位城镇垄断性较强,城镇体系首位度较高;城镇规模级别不合理,存在中间层次的断层现象;城镇体系的基尼系数远离平衡状态,产业梯度转移链条断裂。     

On the distribution of city sizes

The city size distribution in many countries is remarkably well described by a Pareto distribution. We derive conditions that standard urban models must satisfy in order to explain this regularity. We show that under general conditions urban models must have (i) a balanced growth path and (ii) a Pareto distribution for the underlying source of randomness. In particular, one of the following combinations can induce a Pareto distribution of city sizes: (i) preferences for different goods follow reflected random walks, and the elasticity of substitution between goods is 1; or (ii) total factor productivities of different goods follow reflected random walks, and increasing returns are equal across goods.     

中国城市规模分布实证研究

选择1994-2004年中国城市规模位于前200住的地级及地级以上城市,分剐采用人口和建成区面积来表征城市规模,借助于分形理论进行研究发现,无论是从人口规模还是从用地规模来看,中国城市规模的分布符合"位序一规模"法则;外来人口的增加和2000年之后城市规模的加速增长使城市发展表现出向高位次城市集聚的倾向;但由于中国城市体系规模结构比较成熟,其基本特征并没有因时间、外来人口和城市规模的变化而改变;高位次城市仍有较大的发展空间.认为如何更好地识别城市的实际规模,促进城市的理性增长和城市规模结构的健康优化,是中国城市发展亟待解决的问题.     

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.     

US city-size distribution and space

ABSTRACT

This paper focuses on spatial city-size distribution in the United States. It proposes a new distance-based approach to analyze the influence of distance on the city-size distribution parameter by considering the Pareto distribution and using data from different definitions of US cities in 2010. Considering all possible combinations of cities within a 300-mile radius, the results indicate that the Pareto distribution cannot be rejected in most cases regardless of city size. Placebo regressions validate the results, thereby confirming the significant effect of geography on the Pareto exponent.     

The size distribution of cities: An examination of the Pareto law and primacy

This paper examines the Pareto and primacy measures of the size distribution of cities. The mean Pareto exponent for a sample of 44 countries is 1.136, somewhat greater than the exponent of one implied by the rank-size rule. We find that value of the Pareto exponent is quite sensitive to the definition of the city and the choice of city sample size. The significance of non-linear terms in variants of the Pareto distribution also indicate that the rank-size rule is only a first approximation to a complete characterization of the size distribution of cities within a country. The relatively low correlation between primacy and Pareto measures confirms the need for a variety of measures of city size distributions. This paper also suggests that large cities are growing faster than small cities in most of the countries in our sample. This is indicated by the positive coefficient on the first non-linear term introduced into the Pareto equation. Finally, variations in the Pareto exponent and measures of primacy are partly explained by economic, demographic, and geographic factors.     

Sequential city growth: Empirical evidence

Using two comprehensive datasets on populations of cities and metropolitan areas for a large set of countries, I present three new empirical facts about the evolution of city growth. First, the distribution of cities’ growth rates is skewed to the right in most countries and decades. Second, within a country, the average rank of each decade’s fastest-growing cities tends to rise over time. Finally, this rank increases faster in periods of rapid growth in urban population. These facts can be interpreted as evidence in favor of the hypothesis that historically, urban agglomerations have followed a sequential growth pattern: Within a country, the initially largest city is the first to grow rapidly for some years. At some point, the growth rate of this city slows down and the second-largest city then becomes the fastest-growing one. Eventually, the third-largest city starts growing fast as the two largest cities slow down, and so on.     

中国城市集聚与扩散的转换规模及最优规模研究

以我国211个主要地级及地级以上城市为研究对象,其中包括除拉萨以外的30个省会城市、5个计划单列城市以及176个地级市.收集了1989-2003年及2000-2005年各城市的连续时间序列数据,构建了城市集聚与扩散的Panel-data模型,并运用该模型分别估算了各城市的相对规模收益和相对外部成本,然后通过收益与成本的对比分析,判断城市发展所处的阶段,找出城市以集聚为主向以扩散为主转换的城市规模.研究发现:目前,除上海市处于扩散阶段外,我国其它城市都处于以集聚为主的发展阶段,且在这些城市中,绝大部分城市的规模收益的增长速度要快于其外部成本.     

京津冀区域空间格局及其优化整合分析

本文以京津冀区域空间结构为研究对象,从点、线、网络和域面四个基本空间要素入手,研究提升区域竞争力的空间整合规律.研究认为,京津冀区域人口和城镇体系的空间分布不均衡,一方面,以自然条件为基础,呈现东南集中特征,另一方面,中小城镇分布以京广、京九、京哈铁路等为依托,呈现以北京为中心的强向心分布;城镇带分布大体可划分为京广线...     

高铁时代的城市经济增长路径与效益机制研究

本文基于综合的分析框架,探讨高铁对城市经济增长的影响及内在机制,并在不同规模城市之间进行比较;使用列车数作为城市高铁建设与运营水平的指标具体考察两种连接方式的不同影响,结合随机森林方法和样本划分进行了机制验证。结果显示,高铁的城市经济效益主要是一种间接影响,作用路径的不同解释了高铁对不同规模城市影响程度的差异性;随着城市规模的扩大,高铁在提高服务业生产效率和促进产业升级方面作用显著,而对于规模较小的城市,高铁的影响主要在于加速产业结构调整;从连接方式看,外向型交通网络的发展能够从多个方面提升大城市的经济绩效,而与邻近城市联系的加强对于中、小城市的发展显示出了积极的影响。     

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.     

基于用地效率分析的城市区域空间结构极化模型及空间发展战略

不同规模的城市其用地效率具有一定的差异性.本文通过对中国660余个不同规模城市的用地效率分析,在总结和分析了传统城市区域空间结构基本理论和模型的基础上,提出基于城市用地效率分析的城市区域空间结构极化模型.通过理论与实证分析表明,城市发展的方向一极是大型化,发展成为特大城市或超大城市(人口100万-400万);另一极是小...     

One-stage structural models to explain city size

Several papers have estimated the parameters of Pareto distributions for city sizes in different countries, but only one has attempted to explain the differing magnitudes of these parameters with a set of country-specific explanatory variables. While it is reassuring that there has been some research which advances beyond simple “curve-fitting” to explore the determinants of city size distributions, the existing research uses a two-stage OLS method which yields invalid second-stage standard errors (and, consequently, questionable hypothesis tests). In this paper, we develop candidate one-stage structural models with normal and non-normal errors which accommodate truncated size distributions, potentially Pareto-like shapes, and city-level variables. In general, these new models are nonlinear in parameters. We illustrate with data on U.S. urban areas.     

我国城市规模两极分化的现状与原因

在城市化过程中,城市规模的分布与资源配置状况对我国经济能否平稳发展有至关重要的作用。运用城市成本—收益、位序—规模分布、网络城市等理论,通过分析我国不同规模城市的人口、经济总量、资源配置等数据,对我国城市规模两极分化的特征性事实做了概括总结,并从市场选择、政治制度、自然历史因素等三个方面分析了我国城市规模两极分化的原因,认为城市化的均衡发展对我国经济社会的平稳发展具有至关重要的作用,并据此提出引导教育、医疗等优质资源向中小城市流动,促进不同规模城市协调发展的对策。     

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。     

The effects of city size and moving costs on public project benefits

This paper uses a simulation model to investigate the benefits of an urban public project when the size of the system of cities (or regions) in which migration occurs can vary and when moving costs impede migration. The model captures the range of possibilities between the perfectly open and closed city cases. We find that the total number of households migrating between cities declines sharply as moving costs rise. Also the level and distribution of project benefits between renters and landowners in the project city and other cities is sensitive to both the level of moving costs and the size of the urban system. The total benefits of the project fall by half or more when moving costs are introduced, even when moving costs themselves are netted out.     

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.     

An indirect test of efficient city sizes

This paper develops a model which demonstrates necessary conditions for efficient distribution of labor across areas given the presence of agglomeration economies and congestion externalities. An indirect empirical test for efficient allocation is formulated based on a comparison of estimated agglomeration economies with the compensating variation in occupation-specific wages needed to attract workers to larger cities. The results of this test suggest that there are specific city size ranges where necessary conditions for efficient allocation of resources are not met, particularly for cities in the 1.5 to 2.5 million population range. Current claims that continued growth of the largest U. S. cities is inefficient are not confirmed by the empirical results.     

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.     

基于分形理论谈安徽沿江环湖城市群的建立

简要介绍了分形理论的原理,运用分形理论,借助于罗特卡公式分析安徽省城市体系规模分布的分形特征,发现安徽省城市体系规模分布符合位序—规模率,存在城市体系规模分布过于均衡及首位城市、大城市规模过小的问题。提出建立安徽省沿江环湖城市群规模体系的发展对策。