Mapping Market Areas Using Nonparametric Smoothing

A new method is proposed to map firms' principal market areas using shipment data. The new method is a general one which could prove just as useful in mapping the incidence of disease as in mapping market areas. This method is applied to agricultural data for feeder cattle sales at a video cattle auction. Transportation costs appear to be the main determinant of market area boundaries, but there are many cases where transportation costs alone cannot explain the market areas found. The size and shape of market areas for feeder cattle buyers are large, irregularly shaped, and extensively overlapping.     

MILL AND UNIFORM PRICING A COMPARISON*

ABSTRACT. In this paper we examine profit, price, output and welfare under mill and uniform pricing in a monopolistic spatial market with nonlinear demand, a general consumer distribution function, and a general transportation cost function. We show that if demand is convex (concave) then the optimal uniform price minus the average unit transportation cost is lower (higher) than the optimal mill price, output under uniform pricing is lower (higher) than output under mill pricing, and welfare under uniform pricing is lower (higher) than welfare under mill pricing, provided other respective conditions are satisfied.     

论区域旅游发展中旅游区与行政区的矛盾与融合

旅游区与行政区在区域划分目的、区域划分方式等方面存在着本质上的差异,这种差异造成了旅游区与行政区在区域旅游发展的运作与管理中的诸多矛盾,阻碍了区域旅游业的发展。本文阐述了旅游区与行政区的本质与差异,分析了旅游区与行政区在区域旅游发展中的矛盾,研究了如何消除这些矛盾,并通过利益的协调达到区域间的融合。     

SPATIAL ENTRY DETERRENCE UNDER OLIGOPOLY*

ABSTRACT. This paper examines colluding, oligopolistic firms in a linear market. By assuming that rivals do not compete for consumers at their market boundaries, it is shown that an equilibrium exists without adopting a convex transportation cost function. Two price profiles are derived. The first describes firm prices in the absence of threatened entry. The second details profit-maximizing prices which forestall entrants. Given infinite relocation costs, threatened entry leads to price adjustments by the incumbent firms.     

MARKET DEFINITION AND ASSESSING THE COMPETITIVE RELATIONSHIP BETWEEN RAIL AND TRUCK TRANSPORTATION*

ABSTRACT. In this paper we develop a method for establishing market definition in studies of intermodal competition. We employ the proposed method in a transportation model that yields estimates of the substitutability between truck and rail services for the transport of fresh fruits and vegetables. The model includes the produce being shipped as an input into the production of delivered produce. Our results demonstrate that fairly disaggregate market definitions are required to characterize adequately the intermodal substitution possibilities of interest. While disaggregate data are required for econometric estimation of the cost function, it is essential that elasticities be calculated at a disaggregate level as well. The elasticities reported are larger than reported in earlier work and provide strong evidence of vigorous intermodal competition in produce transportation markets.     

城乡一体化过程中聚落选址和布局的演变

城乡一体化是区域经济发展到一定阶段的产物,它在客观上表现为聚落选址和布局的演变:即在发达地区表现为居民聚集区由点状分布趋向面状分布,在欠发达地区表现为由点状分布趋向线状分布。这种聚落选址和布局的演变是城乡一体化过程中经济发展的必然结果,受着影响经济发展的因素的制约;然而,聚落选址和布局演变又是影响经济发展的一个重要因素,制约着区域经济的发展。在城乡一体化过程中,现代交通取向,现代市场取向、现代工业取向和现代人口取向是聚落演变的重要推动力,影响聚落选址和布局的基本格局。不同的聚落选址和布局对区域经济的发展有着加速或延缓的作用。     

上海大都市区物联网产业集聚与空间演化

新兴技术产业的空间集聚与扩散对大都市区的空间结构有直接的影响,厘清新兴技术产业的空间分布和区位选择规律对新兴产业集群培育和大都市区空间结构调整都具有重要的政策意义。本文分析了上海市物联网企业的空间分布和集聚特征,结果发现初创期物联网企业在郊区集聚,随后向郊区其他区域扩散,并呈现出从单极向多极集聚转变的空间演化进程。通过构建负二项回归探究上海物联网企业的区位选择因素,结果表明制度因素和企业集聚效应对企业区位选择有重要影响。在产业发展初创期,企业区位选择受政府管制和市场机制双重影响,其中制度因素发挥了关键作用;而在随后的兴起期,产业集聚效应对新企业的入驻具有强大的吸引力。     

城市化进程中交通公平的研究进展

在系统分析城市化进程中交通公平内涵的基础上,从弱势群体与社会排斥、交通公平评估与改善策略等方面,梳理交通公平的相关研究成果。结果表明,当前城市交通公平性研究还需从以下几个方面进行完善:交通公平内涵应更加注重改善快速城市化地区居民群体的出行环境;系统分析快速城市化进程中交通公平的演化模式,改善交通公平的基本测度方法;构建交通公平评估的空间分析方法,从经济成本可达性角度剖析交通公平性;关注快速城市化地区交通公平的改善策略,提出可操作性的交通公平优化方法。     

SPATIAL PRICE POLICY AND THE DEMAND FOR TRANSPORTATION

For a spatial market of given radius transportation cost per unit sold is less under mill pricing than under any uniform pricing. This is true whether profit-maximizing monopoly prices or welfare-maximizing prices or any other prices are chosen.     

Pastoralism and Protected Area Management in Mongolia's Gobi Gurvansaikhan National Park

The Gobi Gurvansaikhan National Park was established in south central Mongolia in 1993 and is used by over 1100 families with pastoralism as their main means of livelihood. Research conducted in 1998–2000 to analyse grazing management problems identified a number of issues and concerns, including a significant increase in the number of herders and the size of the herd; variations in herd size reflecting differences in wealth; problems with marketing of livestock or livestock products; declining stock movements because of transportation costs and loss of water sources; and significant competition and conflicts for grazing areas. The socio‐economic problems associated with Mongolia's transition to a market system, coupled with the expansion of protected areas, mean that herders have to adapt to both the current economic system and changes in land use. Although some aspects of the development of the park can be seen as a positive influence on maintaining pastoral livelihoods in this area, the national goal of protecting 30 per cent of the country, doubling the area of Mongolia currently under protected area status, could have negative effects on pastoral livelihoods, unless ministry officials, protected area administrators and pastoralists can work effectively to solve resource problems.     

大都市区居民对新兴边缘城市的认知与迁居意向——以天津大都市区为例

目前天津经济技术开发区(TEDA)已发展成为天津大都市区的新兴边缘城市。本文以居民问卷调查的第一手资料为基础,分析天津大都市区内各地区居民对TEDA的认知程度与迁居意向以及地域选择性特征,为以TEDA为核心的人口反磁力中心建设为主导的天津大都市区人口调整对策提供科学依据。     

天津——近代北方经济的龙头

具有优越地理区位、便利交通条件和良好经济基础的天津,开埠后又利用通商口岸所特有的宽松环境、发展机会和广阔市场,逐步成为北方最大的对外贸易中心、工业中心和金融中心,成为近代北方经济的龙头,极大地推动了北方广大地区经济的现代化进程。真正充分发挥港口城市天津所固有的巨大经济优势和潜力,有利于今天北方市场经济的全面、健康、快速发展。     

开发区社区居民日常活动空间研究——以北京经济技术开发区为例

基于社区问卷调查数据,从行为主义视角对北京经济技术开发区社区居民的通勤、购物、就学、就医、休闲等日常活动空间开展实证研究,刻画开发区职住分离、购物行为的空间指向性,以及居民就学、就医和休闲行为的空间分配特征。继而,基于加入空间变量的消费者效用函数,结合转型期城市空间重构背景,重点从居民需求、市场供给和政府供给相互作用的角度对开发区社区居民日常活动空间特征进行解释,并概括出其形成的综合机制模式。研究发现,距离、业态偏好、对服务设施质量的要求,以及交通方式改善带来居民需求变动,与市场供给的空间分布、政府供给的相对短缺共同影响,塑造了社区居民的日常活动空间。     

中国优秀旅游城市空间分异及影响机理研究

运用最邻近指数和ESDA方法,对1998、2004、2010年我国优秀旅游城市的时空差异进行分析。研究结果表明:①空间分布上,呈"东密西疏"的分布格局,沿交通干线、内河流域及海岸线分布特征明显;时间演化上,表现由东部沿海逐渐向中部、东北部扩散的时序规律。②空间分布类型呈集聚态势,区域分布均衡度较低。③空间分布存在显著的正相关特征,总体趋势不断减少,低-低集聚不断增强。④重心增长空间格局的发展态势不稳定,热点区和冷点区表现出一定的梯度性。最后,指出人口分布、经济水平、旅游资源和区位条件四个方面是影响我国优秀旅游城市空间分异的重要因素。     

A GENERAL FRAMEWORK FOR THE INTEGRATION OF A LAND-USE MODEL WITH A TRANSPORTATION MODEL COMPONENT

Integrated land-use—transportation models are characterized as models in which the redistributive effects of one subsystem upon the other are explicitly defined and incorporated into the model's structure. At the core of integrated models is a linking procedure whose function is to transform the outputs of one model component into inputs for the other. Despite major efforts made in the past to build operational large scale integrated models, the structural properties of such models remain largely unexplored. This paper describes a general framework for an integrated model consisting of prototype model components. These are an iterative activity allocation model of the Garin-Lowry type, an equilibrium-assignment transportation network model, and a linking procedure. Given the level of analysis, this framework is shown useful for exploring the analytics of integrated models and, in particular, their equilibrium properties. By means of many simulation experiments based on an hypothetical numerical example, the operation of the model is demonstrated with an emphasis on the locational interpretation of the integration procedure. On the basis of the empirical results and considering the model's intrinsic assumptions, the following major findings can be cited. First, the effects of nontravel factors (such as basic employment and zonal attractions) upon activity distribution are stronger than effects caused by changes in the transportation system. The latter effects were found to yield nonlinear and, spatially, nonuniform changes in activity location which also tended to be larger in peripheral regions. Second, implicit in the specification of the integration procedure are behavioral assumptions regarding time-lags in locational adjustments made by activities in reaction to rising cost of travel. The present formulation implies that once located, activities do not revise their locational decisions despite substantial increases in travel costs. At the other extreme, all activities are permitted to readjust their locational preferences after the final interzonal travel costs are derived. The effect upon activity distribution of the latter specification is, of course, larger than that of the former, although less than the effect yielded by changes in nontravel factors. Regarding the equilibrium properties of the integrated system, both the theoretical and empirical analyses show that the entire model will converge into an equilibrium solution and that the corresponding trip patterns are also at equilibrium. These results will hold as long as the operation of the integrated models is completely controlled by the generation functions of the land-use model and the transportation model component only affects the spatial distribution of activities. Finally, the results from the simulation experiments indicate that the computed mean travel cost parameter tends to stabilize around a certain value as the level of demand for travel, within the system, rises. There is evidence that compensating changes in the location and composition of this demand are the main causes of this phenomenon. In light of these findings, it is possible to point to three key problems whose resolution could largely improve the predictive power of integrated models. First, it would be useful to define activity models in which the generation of activities is, among other things, a function of travel conditions. Second, currently formulated integrated models do not contain trip demand functions and, thus, demand for travel by an activity unit is regarded as completely inelastic. Third, different locating activities respond differently—over time and space—to changíng travel conditions, and models should, therefore, reflect explicitly such differences in activity behavior. A recent paper by Los [14], is an important contribution to the analysis of this issue.     

URBAN UNEMPLOYMENT AND THE SPATIAL STRUCTURE OF LABOR MARKETS: AN EXAMINATION OF THE “TODARO PARADOX” IN A SPATIAL CONTEXT*

ABSTRACT The Todaro paradox and the effects of job creation in urban areas will be re-examined in our spatial model in which the radius of the labor market is endogenously determined by the rational choices of workers. The travel cost of workers plays a crucial role in the choice between two different types of response, migration or commuting. By considering travel costs, we find that the Todaro paradox can be applied to developed, as well as developing, countries. Job creation in urban areas can produce a paradoxical increase in urban unemployment in developed countries, because the low marginal cost of travel will significantly increase the radius of the urban labor market and create new labor supply without migration.     

中部农区农户打工距离研究——以河南三个样本村为例

对农户打工距离和区位的研究是认识农民工流动空间规律的基础。通过对河南省三个不同类型样本村的实证研究,发现打工距离整体分散、局部集中,打工人数随距离的变化呈"U"型分布,打工者在打工目的地的分布上具有群聚特征。影响农户打工距离选择的主要因素是年龄、家庭类型、家庭代数、上学人数和关系网络因子。年龄较大者、家庭类型较简单者、家庭代数较多者、上学人数较多者和关系网络较少者,选择在本地打工的概率较大,反之亦然。     

An Evolutionary New Economic Geography Model

In this paper we present a general new economic geography model with multiple industries and regions, full labor and capital mobility, land use in production and consumption, and a dynamic adjustment process in which consumers maximize utility and firms respond to nonzero profits. All industries use intermediate inputs as well as land, labor, and capital. Systems of cities form endogenously within this framework, including asymmetrical urban hierarchies and cities of different sizes and industry compositions. Each urban area has a bid-rent gradient and zones with land uses and densities as in the von Thünen model. The equilibrium depends not only on initial conditions but also on speeds of adjustment. The model is a prototype for empirical implementation, as illustrated with a simulation of the effects of transportation cost reductions.     

Residential planning,driver mobility and CO2 emission: a microscopic look at Borlänge in Sweden

In a city there are hotspots that attract citizens, and most of the transportation arises when citizens move between their residence and primary destinations (i.e. hotspots). However, an ex ante evaluation of energy-efficient mobility and urban residential planning has seldom been conducted. Therefore, this paper proposes an ex ante evaluation method to quantify the impacts, in terms of CO₂ emissions induced by intra-urban car mobility, of residential plans for various urban areas. The method is illustrated in a case study of a Swedish midsize city, which is presently preoccupied with urban planning of new residential areas in response to substantial population growth due to immigration. In general, CO₂ emissions increase from the continued urban core area (CUCA), to the sub-polycentric area (SPA), to the edge urbanization area (EUA), where CO₂ emission of EUA is twice that of the CUCA. The average travel distances also increase in the same pattern, though the relative increase is more than four times. Apartment buildings could be more effective in meeting residential needs and mitigating CO₂ emissions than dispersed single-family houses.     

中国大城市旅游休闲业态的空间格局研究：西安案例

明确大城市旅游休闲业态的分布规律对于提高大城市旅游休闲要素配置效率及完善城市现代服务业体系具有重要意义。本文以机构兴趣点（POI）数据为基础,利用最邻近距离指数、核密度估计及地理探测器等空间分析方法,以西安市为案例探究中国大城市旅游休闲业态空间格局的规律性。结果表明,西安城市旅游休闲总体业态和细分业态均表现为在城市中心局部多核集聚,且业态密度由城市中心区向边缘区梯度递减的分布结构。而这一规律实则为消费市场、CBD区位、经济水平和路网密度等因素综合作用的结果。文章认为,为提高大城市旅游休闲产业要素配置的均衡性与高效性,城市管理者需兼顾城市中心及外围区域的统筹发展,并应在消费引导、资本投入、功能区建设和基础设施优化方面加大对外围区域的支持力度。