徐州都市圈城市体系结构分析

基于2005年统计数据,运用分形理论及GIS技术,从规模结构、空间结构、职能结构三方面,对徐州都市圈城市体系的结构进行分析。结果表明:徐州都市圈城市规模等级结构明显,城市首位度高,小城市发展滞后;城镇密度分布呈带状延伸的特征,空间结构呈较典型的港城"双核结构";城市职能结构单一,类型趋同,资源型城市比重大,属于工矿型城镇体系。最后提出优化徐州都市圈城市体系结构的对策和建议。     

The topography of metropolitan employment: Identifying centers of employment in a polycentric urban area

While it is well recognized that US metropolitan areas are polycentric, there is little consensus as to the appropriate method for identifying concentrations of employment within them. Existing methods suffer from strong assumptions about parametric form, misspecification, or reliance on local knowledge to calibrate model parameters. This paper introduces a new nonparametric method for identifying subcenters. Results indicate that this, more flexible, nonparametric approach yields greater accuracy with regard to both urban and suburban centers compared with other approaches. This approach should provide better data for the numerous topics that depend on the spatial accounting of employment within metropolitan areas.     

京津冀都市区统计与当前城市统计的比较研究

近年来,随着京津冀地区城市化进程的快速推进,中心城区不断向外扩张,加上周边农村地区的发展,城乡之间的经济与社会联系加强,都市区逐渐形成并发展。对京津冀都市区发展状况进行分析,在此基础上将都市区统计和当前城市统计进行对比,发现都市区是人口和经济活动的主要聚集地,是真正具备城市功能的地域;都市区代表了区域内更高的产业结构和发展水平;都市区统计能够更好地反映城市化快速发展的状况。最后总结了中国建立规范的都市区统计制度的必要性和迫切性,并从都市区的视角提出了促进京津冀区域内产业协调发展和统筹城乡发展的策略建议。     

Community income distributions in a metropolitan area

We extend de Bartolome and Ross [C.A.M. de Bartolome, S.L. Ross, Equilibrium with local governments and commuting: Income sorting vs. income mixing, Journal of Urban Economics 54 (2003) 1–20] to the case when the income distribution in the metropolitan area is a continuous distribution. In particular, we consider a circular central city surrounded by a suburban community. All households must commute to the metropolitan center and public service levels differ in the two jurisdictions. There is intra-jurisdictional and inter-jurisdictional capitalization. Our model has an equilibrium in which the income distributions of the central city and of the suburban community do overlap. Our finding contrasts with the traditional finding of Alonso–Mills–Muth-type models of spatial sorting and of Tiebout-type models of fiscal sorting, both of which have been shown to predict that the income distributions of the two communities do not overlap. In addition, the model explains the fixedness in jurisdictional boundaries.     

Household location in a linear multi-center metropolitan area

The application of monocentric models of residential location to the analysis of metropolitan areas with more than one center of economic activity, produces a distorted view of the spatial distribution of urban variables such as land values, housing prices, etc. This distortion results from the fact that monocentric models tend to underestimate the values of these variables in areas lying between the centers, and yield wider residential areas toward the outskirts of the city. In this paper, a model of household location is developed, which attempts to correct this distortion by simultaneously considering the urban centers during the residential location process.     

Spatial patterns of urban growth: Optimum and market

The optimum spatial pattern of urban growth for a problem which is essentially a dynamic version of von Thünen model of land use is first studied by using a notion of bid land price curves, which is a dynamic extension of bid rent curves by Alonso [1]. Then a competitive market of which equilibrium growth path coincides with this optimum one is obtained by examining demand side properties. It is hoped in this way to throw some light for the future development of dynamic theory of urban land use.     

Job creation and housing construction: Constraints on metropolitan area employment growth

Differences in the supply of housing generate substantial variation in house prices across the United States. Because house prices influence migration, the elasticity of housing supply also has an important impact on local labor markets. I assemble evidence on housing supply regulations and examine their effect on metropolitan area housing and labor market dynamics. Locations with relatively few barriers to construction experience more residential construction and smaller increases in house prices in response to an increase in housing demand. Furthermore, housing supply constraints alter local employment and wage dynamics in locations where the degree of regulation is most severe.     

On the analysis of multivariate growth curves

Growth curve data arise when repeated measurements are observed on a number of individuals with an ordered dimension for occasions. Such data appear frequently in almost all fields in which statistical models are used, for instance in medicine, agriculture and engineering. In medicine, for example, more than one variable is often measured on each occasion. However, analyses are usually based on exploration of repeated measurements of only one variable. The consequence is that the information contained in the between-variables correlation structure will be discarded.  In this study we propose a multivariate model based on the random coefficient regression model for the analysis of growth curve data. Closed-form expressions for the model parameters are derived under the maximum likelihood (ML) and the restricted maximum likelihood (REML) framework. It is shown that in certain situations estimated variances of growth curve parameters are greater for REML. Also a method is proposed for testing general linear hypotheses. One numerical example is provided to illustrate the methods discussed. Received: 22 February 1999     

Coexistence and segregation of two groups in a metropolitan area through externalities

This paper proposes to regard the population distributions of two groups in a metropolitan area as equilibrium solutions of systems of ordinary differential equations. This approach—an extension of the Miyao's single subarea model to a many subarea case—allows us to incorporate the effect of fiscal/pecuniary neighborhood externalities into the classic Alonso-Mills-Muth model. This paper investigates its three typical cases, and obtains one coexistent and two segregated solutions. Consideration on these cases leads to the conclusion that substantial neighborhood externalities other than simple tax redistribution exist between the groups in the United States. As by-products of this analysis, it is also shown that positive bid gradients and discontinuities of bid prices are realized under suitable conditions.     

Dynamics of metropolitan growth and unemployment

The author presents a demand-oriented model of metropolitan growth with explicit regard to urban unemployment and spatial growth. The long-term behavior of several factors, including population, is examined in response to exogenous demand growth for output     

A comparison of parametric and non-parametric efficiency measures: The case of Norwegian ferries

The trunk road system in Norway has to be supplemented by a number of ferries due to the long coastline with numerous islands and fjords. Most of the ferries are run by private companies, but at a loss. The deficit are covered by the Ministry of Transport. The subsidies have risen rapidly in the last years and have focussed attention on whether the ferries are really run as efficiently as possible. To change the incentives to economize, a lump-sum payment is considered. To implement such a system, an initial assessment of reasonable input requirements is needed. The aim of this article is to provide such a yardstick by establishing a best practice frontier. Both a non-parametric and a parametric approach to a deterministic frontier are tried and differences of results discussed. Peculiarities due to choice of methods are revealed. The efficiency distributions are quite similar for the two methods except for scale efficiency, where the parametric method indicates substantial unrealized scale economies, while the non-parametric approach shows the largest and some small ferries to be scale efficient. The results indicate a substantial rationalization potential of about 30 percent in total.I am indebted to three referees for forcing me to improve significantly the quality of the study. Any remaining shortcomings are, of course, my responsibility.     

An empirical model of residential location and the journey-to-work in a metropolitan area

In this paper we present and estimate a single equation model designed to explain the residential location behaviour of individuals living in a multi-centered metropolitan area. We test the model for heads of households and non-heads of households separately, as well as for the total working population, in order to isolate differences in commuting behaviour between primary and secondary wage earners. The relationships are estimated from 1971 Census, cross-section data using least squares multiple regression. The data pertain to the Toronto Census Metropolitan Area (CMA) and sixty-three designated zones therein.The estimation results reveal that although location-rents prove to be significant in the individual's residential location decision-making process, their effect was limited to discouraging those employed in or near the central business district (CBD) from living close to work. The existence of secondary employment centres did not have the same significant effect in bidding up location-rents. Furthermore, contrary to the standard theory, the results suggest that residential location decisions are made in response to the availability of collective residential opportunities and workers' preferences for specific residential attributes rather than by reference to the “transportation cost—housing cost” trade-off. Among the socio-economic variables, age of the worker is found to be most significant in affecting journey-to-work distance. The results provide some evidence that non-heads are, to a certain extent, more sensitive to urban structural constraints in their commuting behaviour.     

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.     

北京大都市住宅郊区化的基本特征与对策

本文在分析 1992— 2 0 0 0年北京地区住宅用地统计资料的基础上 ,针对北京日益突出的住宅郊区化现状 ,找出其扩展的规律 ,预测近 2 0年的发展趋势 ,最后提出合理引导城市郊区化的措施及对北京城市建设的建议。     

Wavelet analysis of change-points in a non-parametric regression with heteroscedastic variance

In this paper we develop wavelet methods for detecting and estimating jumps and cusps in the mean function of a non-parametric regression model. An important characteristic of the model considered here is that it allows for conditional heteroscedastic variance, a feature frequently encountered with economic and financial data. Wavelet analysis of change-points in this model has been considered in a limited way in a recent study by Chen et al. (2008) with a focus on jumps only. One problem with the aforementioned paper is that the test statistic developed there has an extreme value null limit distribution. The results of other studies have shown that the rate of convergence to the extreme value distribution is usually very slow, and critical values derived from this distribution tend to be much larger than the true ones. Here, we develop a new test and show that the test statistic has a convenient null limit N(0,1) distribution. This feature gives the proposed approach an appealing advantage over the existing approach. Another attractive feature of our results is that the asymptotic theory developed here holds for both jumps and cusps. Implementation of the proposed method for multiple jumps and cusps is also examined. The results from a simulation study show that the new test has excellent power and the estimators developed also yield very accurate estimates of the positions of the discontinuities.     

区域规划与大都市地区的公共服务供给——以美国明尼苏达州双城大都市区为例

区域规划是大都市地区公共服务供给的重要工具。区域规划需要法律、制度化的政治和财政为基础,其制度化程度越高,公共服务的效率就越高。美国双城地区的大都市理事会,作为有效区域规划机构的典型,其发展证明了州政府是区域规划机构有效运行、大都市区公共服务有效供给的关键因素。     

宁国巨变——写在6年后重访宁国之际

当确定用<宁国巨变>来作我们这篇文章的标题时,我们心感有点自不量力.因为这样评语式又肯定性的标题.应该出自大人物之手或之口才合适,可我们琢磨来琢磨去,脑子里总难于寻找到更为合适的词汇来表述宁国今天的发展变化.因而.我们只能将自己的所见、所闻、所思跃然于本文的字里行间.宁国是否巨变,请读者自己评说.     

城市功能地域概念及其在规划中的应用

从提出背景、空间组织、空间形态与结构、城市功能特征等四个方面对城市功能地域的概念进行了辨识,分析了都市区、大都市带、都市圈、城市群、经济圈等概念,对城市功能地域发生作用的内部机理和规划中要解决的问题进行了分析,并对城市功能地域的概念在城市规划中的应用提出了建议。