CHANGES IN ACCESSIBILITY TO EMPLOYMENT IN AN URBAN AREA: MILWAUKEE, 1927–1963

Data from transportation studies are used to examine changes in accessibility to employment opportunities in the Milwaukee urban area from 1927 to 1963. Low-status areas of the city tended to experience the greatest decreases in employment accessibility compared with other parts of the urban area. Furthermore, increasing levels of employment accessibility were associated with greater amounts of new housing, whereas decreases in housing vacancies and population occured in areas with declining accessibility to employment.     

Amenity value in post-industrial Chinese cities: the case of Nanjing

Many Chinese cities are in a transition from industrial to post-industrial urban economies. In this process of urban restructuring, land use becomes polycentric and fragmented. More sophisticated models are needed to estimate the amenity effects of this complex residential environment. This article assesses the relative housing price effects of neighborhood characteristics and accessibility in Nanjing, China. This is achieved with a hedonic price model that incorporates detailed spatial measures, geographical contingency, and a modified version of Alonso’s (1964) general theory of land rent. A crucial finding is that the effect of job accessibility on house price varies depending upon the specific sector of employment. Accessibility to jobs in the public and private service sectors has strong positive effects. However, housing proximity to heavy industries has a spatially nonlinear effect: negative in close proximity, but positive at a larger distance. Second, when we control for job accessibility, access to public transport has an added positive effect. Finally, neighborhood “quality” (defined in terms of nearby amenities) is also relevant, but far less than access to service employment. This research shows that Nanjing’s housing prices are affected by different residential characteristics than those with dominant price effects in Western cities.     

Exploring Metropolitan Accessibility and Urban Structure

Location-based assessments of accessibility gauge the attraction of a place relative to other places. These approaches have been used extensively in models of commuting and urban structure. Even though locational accessibility measures are integral to such efforts, they may also be used to explore aspects of urban spatial structure. As such, this paper presents a GIS-based analysis of locational accessibility for a sample of U.S. metropolitan areas. Indices of accessibility based on spatial interaction models are developed for intraurban residential and employment locations. Results show that residential accessibility patterns are similar across cities, taking a concentric pattern where the central urban area is most attractive. However, employment accessibility varies more from city to city; moreover, the areas of highest employment accessibility tend to be decentralized within their respective regions. Overall, location-based accessibility indices are useful for exploring urban form, particularly with respect to issues of urban sprawl. Directions for future research are identified, including linking comparative urban accessibility measures to ongoing work on commuting, the jobs-housing balance, and urban structure.     

Jobs and the Single Parent: An Analysis of Accessibility to Employment in Toronto

Abstract

In this article, we undertake an analysis of accessibility to jobs from the perspective of single-parent household members. Individuals in this demographic segment are of interest due to the fact they often face the double burden of household and employment responsibilities. A case study of the city of Toronto in Canada, an urban area that has seen an increase in absolute and relative numbers of single-parent households in recent years, is presented. Analysis is based on the application of relative accessibility deprivation indicators (RADI), which are calculated using model-based estimates of distance traveled for various population segments, as well as employment data for the city and its surroundings. The results of the analysis indicate that there are substantial differences in the levels of accessibility to jobs between members of single-parent households, in particular females, and members of other types of households.     

基于百度热力图的银川市中心城区职住关系研究

“职”和“住”是城市最基本的功能,职住关系反映了城市秩序与效率。以百度热力图、百度路况图所提供的实时动态大数据为依据,配合城区土地利用现状图,分析了银川市主城区职住关系。结果表明：在一个工作日内,上班时间段内,教育、商业用地上的人口聚集力度更大,而在休息时段,居住用地上的人口聚集状况更明显,二者表现出大致反向的趋势。这意味着上班时段内人口大量离开居住区,百度热力下降;而下班时段又返回居住区,百度热力上升,居民在工作地—居住地间存在着节律性的钟摆式流动。上班时间段内人群高度集中的区域大部分是商务中心、城市综合体、高等院校、医院和物流中心等工作地;休息时段人群高度集聚中心由就业中心转为居住区和休闲购物区,说明整个城区存在一定的职住分离。银川市职—住比介于0.34~3.4之间,职住相对平衡;但区域间差异较大。总体来看,城市中心区比外围区的职住平衡更明显。依据职住比,将职关系划分为基本平衡型、 轻微就业倾向型、 严重就业倾向型、 轻微居住倾向型和严重居住倾向型五类。     

Effects of accessibility and environmental health risk on housing prices: a case of Salt Lake County,Utah

While transportation infrastructure can increase housing price by improving accessibility to opportunities, it generates environmental health risks, such as noise and air pollution, which may have negative effects on housing price. However, the combined effects of accessibility and environmental health risk on housing price have not been well examined in the literature, especially in the auto-oriented urban context of the United States. In this study, we use assessed housing value data and the hedonic model to examine the single-family housing market's reaction to accessibility and environment health risks in Salt Lake County, a growing metropolitan area in Utah experiencing significant air pollution. Three regression models are employed with the consideration of spatial effects: ordinary least squares (OLS), spatial lag regression (SLR), and hierarchical linear modeling (HLM, or multilevel modeling/MLM). By controlling for the influences of structural attributes and socioeconomic conditions, we find that the negative impacts (traffic noise and air pollution) of transportation systems on single-family housing prices are greater than the positive impact (accessibility). Single-family residents in Salt Lake County are willing to pay more to reduce environmental health risks than to get better accessibility. These findings are different from what have been found in some dense and compact urban areas in the literature. These findings suggest that people's willingness to pay for minimizing environmental health risks varies across different urban contexts.     

社会公平视角下深圳公园绿地可达性研究

公园绿地是城市中重要的绿色基础设施。针对传统可达性分析微观尺度研究不足和交通成本估计失真等问题,以深圳为例,采用公园绿地矢量数据和基于手机SDK（Software Development Kit,软件开发工具包）定位的人口数据作为供需数据源,基于住房分类数据以城中村、保障房、商品房居民划分社会群体,利用改进的高斯两步移动搜寻法计算得到居住小区尺度的公园绿地可达性社会公平情况。研究发现：① 深圳公园绿地可达性存在社会分异：商品房和城中村可达性较好;公租房和安居房社区公园可达性差;人才住房仅对社区公园可达性高;② 驾车可达性最均衡,公共交通方式下不同住房群体间的可达性差异较大。研究补充了中国城市公园绿地可达性社会公平研究的不足,改进了小尺度可达性研究的数据与方法,为公园绿地规划体系提供反思,并可为深圳城市发展提供政策依据。     

北京城区流动人口扩散格局及驱动机制

基于街道/乡镇尺度人口普查数据,利用GIS空间分析和数理统计方法,从规模、占比、密度和集聚度等4个层面分析北京城区流动人口扩散特征,并揭示其驱动机制。研究发现, 2000~2010年北京城区流动人口规模和密度增加,但流动人口占常住总人口比重和流动人口空间集聚度下降,流动人口呈现明显的空间扩散态势。 北京城区流动人口呈“核-边扩散”格局,城市核心区流动人口规模、密度、占比和空间集聚度不断下降,城市边缘区流动人口规模、密度、占比和空间集聚度逐步上升。 北京城区流动人口的“核-边扩散”格局是经济因素的直接推动、城建因素的间接推动、交通因素的硬性诱导、制度因素的软性诱导等共同作用的结果。     

基于家庭区位需求的城市住房价格模拟分析

目前关于城市住房价格异质性和影响因素研究多侧重于空间位置分析,从城市系统角度刻画住房价格分异现象有待进一步探索。根据“土地利用—交通相互作用理论”,城市空间的发展过程是各类活动通过交通相互作用的过程,本文构建了交通可达性模型,综合全市经济活动空间分布和交通网络评价城市区位条件,并以北京为例,从就业、教育、消费、医疗服务等各方面评价了城市区位条件,在此基础上依据家庭成员结构,模拟分析了家庭区位需求对住房价格的影响。案例研究表明,本模型对房价的模拟可以在全市范围内达到很好的效果;家庭的区位选择决定着住房价格的空间格局;各类活动中就业对北京市房价分布影响最为显著,其次是消费、教育,而医疗服务对住房价格影响相对较弱。此外,本文所提出的模型系统阐述了城市经济活动分布格局对住房价格的影响,经济活动分布发生变化时模拟结果随之变化,因此,本模型可以进一步拓展用于“以业带人”政策实验,模拟分析疏散各类经济活动后住房价格的变化,也为城市房价及土地市场分析研究提供模型方法上的参考。     

芜湖市就业与居住空间匹配研究

借助偏离度指数分析法从宏观层面研究了芜湖市辖区的就业—居住空间匹配状况的变化特点,利用问卷调查数据,从微观角度分析了市区居民通勤的时间、距离、方式及费用。研究结果表明:芜湖市就业—居住空间匹配度趋于下降,核心区为服务业就业主导区,北部以制造业就业为主导功能,南部居住功能占主导,带来各区居住人口和就业人口的空间流动。居民通勤平均距离约为4km,平均时间约为25min,通勤方式以电动车、公交车为主。目前,居民对就业—居住地匹配状况的满意程度总体尚好,还需要采取措施以进一步提高满意度。     

北京市景观可达性与住宅价格空间关联

随着城市居民对住宅环境要求的不断提高,城市景观对城市住宅价格分异影响日趋显著。分析景观对住宅价格分异格局的影响,可为城市住宅空间结构的规划提供依据,为规划与管理部门提供决策参考。以北京城区二手房小区为样本,基于ArcGIS空间分析方法和特征价格模型,探讨景观因素对北京市住宅价格空间分异格局的影响。以主流房地产交易网站二手商品房报价资料为基础数据,共采集到2012 年1 月北京市城六区有效住宅小区样本3174 个,对住宅样点进行空间化处理,并建立住宅空间信息数据库。运用密度分析、空间插值等方法,分析北京市住宅空间分布特征与价格空间分异格局。核密度分布图显示：北京市住宅空间分布呈现显著的向心化与离心化并存现象,总体上以天安门为中心向周边呈衰减趋势,在地铁转换站点形成了多个集聚次中心。在此基础上,从住宅属性、交通因素、区位特征等方面选择主要解释变量,构建地理加权回归模型,对住宅价格影响因素进行分析,重点探讨景观可达性（如绿地、水景、山景等）与住宅价格的关联。结果表明：次中心与住宅价格关联最为显著,绿地、水景、山景与住宅价格存在一定程度关联。其中,山景和高绿化率对住宅价格增效明显;由于水质较差,北京城六区内河流与住宅价格存在负相关;污水处理以及丧葬场所等污染源与住宅价格也存在显著负相关。远离污染源、靠近宜人景观、低容积率、高绿化率是居民选择住宅的需求。     

大连城市绿地可达性对房价影响的差异性分析

研究房价、遥感影像等多源数据,采用邻域分析法和地理加权回归模型分析大连市中山区绿地可达性及其与房价之间的空间相关性。结果表明：① 房价均价14 745.35元/m²,呈环状分布,由沿海向内陆衰减、桂林街道起中心向外围递减;② 研究区内可达性最好的绿地类型是街旁绿地,绿地可达性总体水平最高街道是桂林街道;公园绿地可达性最好的住宅区分布在昆明街道和桃源街道,街旁绿地可达性最好的住宅区分布在桂林街道,附属绿地可达性最好的分布在老虎滩街道,其他绿地可达性最好的分布在桃源街道。③ 不同类型绿地可达性对房价影响作用程度递减排序为：附属绿地、街旁绿地、公园绿地和其他绿地;附属绿地、街旁绿地和其他绿地与房价呈现空间正相关,随着到达绿地距离降低,房价呈现增长趋势;公园绿地与房价呈现负相关,随着到达公园绿地的距离降低,房价呈现衰减趋势。     

Artificial neural networks and geostatistical models for housing valuations in urban residential areas

Property valuation studies often use classical statistics techniques. Among these techniques, the Artificial Neural Networks are the most applied, overcoming the inflexibility and the linearity of the hedonic models. Other researchers have used Geostatistics techniques, specifically the Kriging Method, for interpreting spatial-temporal variability and to predict housing unit prices. The innovation of this study is to highlight how the Kriging Method can help to better understand the urban environment, improving the results obtained by classical statistics. This study presents two different methods that share the general objective of extracting information regarding a city’s housing from datasets. The procedures applied are Ordinary Kriging (Geostatistics) and Multi-Layer Perceptron algorithm (Artificial Neural Networks). These methods were used to predict housing unit prices in the municipality of Pozuelo de Alarcon (Madrid). The implementation of both methods provides us with the urban characteristics of the study area and the most significant variables related to price. The main conclusion is that the Ordinary Kriging models and the Neural Networks models, applied to predicting housing unit prices are necessary methodologies to improve the information obtained in classical statistical techniques.

Abbreviations: ANN: Artificial Neural Networks; OK: ordinary Kriging; MLP: multi-layer perceptron     

The Urban Settlement Patterns of Disadvantaged Migrants

Abstract

Disadvantaged migrants to metropolitan areas are segregated by race, ethnicity, or socioeconomic status within the residential areas of central city poverty neighborhoods. Whereas black migrants are generally restricted to ghetto space, regional cultural similarities and feedback in the social communication network are important to the residential location of lower class whites. The urban settlement patterns of a sample of recent disadvantaged white migrants to Indianapolis, Indiana, vary from the clusters of migrants from Appalachia and the South to the more dispersed pattern of migrants from Indiana, Illinois, and Ohio, and other metropolitan areas. The residential location of migrants from Appalachia and the South is geographically restricted by cultural constraints, and heavy reliance upon a limited network of friends and relatives in the housing search. However, the sociocultural resources of the Midwest group and the previous urban experience of metropolitan migrants increase the range of housing opportunities in Indianapolis that are available and known to them.     

Housing differentiation and housing poverty in Chinese low-income urban neighborhoods under the confluence of State-market forces

ABSTRACT

Based on a large-scale household survey conducted in six large Chinese cities, this study is among the first attempts to juxtapose factors related to institution, market, and demography to examine the complex patterns and mechanisms of housing differentiation and housing poverty in low-income neighborhoods, which are conventionally conceived as homogenous substandard settlements. Results of Theil indices and multivariate regression models convey several interesting findings. First, the forces of the market and the State have projected different impacts on various aspects of housing status. Institutional factors had significant impacts on some costly and durable housing indicators such as housing tenure and housing area, while market forces have swiftly transformed the most malleable aspects of housing conditions, such as housing facilities, and will eventually replace some institutional legacies. Second, within-group housing differentiation is more palpable than between-group housing differentiation, suggesting that low-income neighborhoods in large Chinese cities are fluid and heterogeneous. Third, different institutional elements have different impacts on housing poverty. The well-functioning market remuneration system helps reduce the risk of housing poverty, yet working poor remains a severe problem. These findings can inform policies promoting social mix and housing affordability.     

居民就业可达性的空间分布及对收入的影响——基于上海都市区的实证研究

基于第六次人口普查、第二次经济普查和问卷调查数据,定量描述和分析了上海都市区内部以街道为空间尺度的就业可达性及其空间格局,探讨了劳动者的工资收入与居住区位就业可达性的关系。结论表明：上海市的居民就业可达性呈现相对均衡的多中心分布格局,与北京就业可达性单中心的分布格局有明显的不同。同时,在控制个人经济社会属性和地区属性的条件下,上海的居民就业可达性对居民个人收入水平具有显著的正向影响。这一结论的政策含义是,地理区位较差的住房有损于居民收入,可能是吸引力不足的重要原因之一;政府通过提高地区的居民就业可达性,有助于改善就业机会,促进居民个人收入的增加。     

THE PRODUCTION AND EMPLOYMENT OF GEOGRAPHERS IN CANADA

This paper considers the appropriateness of typologies of urban retailing areas based on multivariate functional data. The findings of a case study in which statistical and graphical methods were employed within the framework of multivariate ordination are presented. It is shown that the functional attributes of retail areas are closely associated with their location, accessibility, quality, morphology, size, period of development, and socioeconomic character.     

LOCATING EMPLOYMENT GROWTH IN URBAN AREAS TO MINIMIZE TRAVEL TIME

The transportation requirements of an urban area are, in part, a function of its land use pattern. Reducing travel in an urban area by effective land use design appears to be a worthwhile public policy objective. The planning model derived in this article uses as its core the matrix version of the Lowry model developed by Garin. The model allocates basic employment to the zones of an urban area in order to minimize work and service trips. A hypothetical planning problem for Metropolitan Toronto illustrates use of the model.     

乌鲁木齐市职住空间组织特征及影响因素

本文借助职住分离指数分析法从宏观层面分析了乌鲁木齐市辖区的职住空间匹配状况,利用问卷调查数据,从微观角度分析了不同类型居住区居民的通勤距离和通勤时间。研究发现：职住空间分离是乌鲁木齐城市空间结构的突出特征;全市职住空间不匹配程度较大,居住主导区的街道有35个,占街道总数的44.3%;就业主导区的街道有25个,占街道总数的31.65%;基本匹配区的街道仅有7个。居住区类型、居民受教育程度、职业类型、收入水平、住房形式等社会经济属性对其职住分离程度均有一定程度的影响;采用GWR模型定量分析了职住空间关系的影响因素,认为学历构成、住房产权性质、职业类型、流动人口以及住房面积是影响乌鲁木齐市职住空间关系的主要因素。     

广州都市区租房户的空间分异与居住选择倾向

城市居民购房与租房的居住选择倾向及其机制存在差异,但当前对租房方面的研究仍显不足。鉴于此,本文构建城市租房户居住选择过程中“好房子、好位置、低租金”不可兼得的“不可能三角”理论框架及其基本理论模型,这为研究租房户居住选择倾向提供了一个新的视角。以广州都市区1328个社区为案例,得出广州都市区的租房户比例呈现核心区低,中心城区和近郊区较高的空间分异格局,并呈现显著的空间关联特征。构建广州都市区租房户居住选择倾向因素指标体系,该体系由租金水平、住房自身条件和区位条件三大类9个指标构成。通过空间误差模型分析表明,广州都市区租房户倾向于居住在低租金水平和房龄较新的社区,且被动选择租住在住房建筑面积较小、住房内部设施较差、日常生活便利性较差的社区中。该结论可丰富和完善中国特大城市居民租房选择理论,为特大城市租赁住房政策制定提供决策参考。