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Samples used to estimate discrete choice models in geography and regional science are typically assumed to be simple random samples. This assumption is not always met with existing samples. Furthermore, data collection is usually less costly if a stratified sampling strategy is adopted. Existing sampling theory suggests that stratified sampling can affect the consistency of parameter estimates. This paper reviews the salient points of this theory and relates theory to practice by means of a simple example on housing choice by elderly.  相似文献   

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In this second report from the Long Range Planning Committee, the Chairman of the Communications Task Force discusses the purpose, structure, and functioning of Specialty Groups, which are to be established in accordance with a Committee recommendation approved by the AAG Council.  相似文献   

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George Martin 《Area》2007,39(1):66-73
The global diffusion of motorization has become a significant driver of local and regional change around the world. In the South (the developing countries), especially in China, the scale of its impact in the twenty-first century carries the potential to dwarf that of motorization in the North (the developed countries) in the twentieth century. While alarms have been sounded about the threat of greatly increased greenhouse emissions posed by China's telescoped development of motorization, this paper analyses its neglected social and ecological impacts. Through an analysis of car and land use data, China's loss of agricultural land and growing social polarization are highlighted.  相似文献   

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This paper questions the validity and relevance of the application of procedures of classical statistical inference to population data in geography. Arguments for such procedures include the notions of temporal and spatial samples, measurement error, modifiable areal units, data vetting and stochastic processes. It is concluded that such arguments cannot be justified in terms of statistical theory.  相似文献   

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《Urban geography》2013,34(2):174-192
Subsistence gardens were a significant land use in the Columbus, Ohio metropolitan area from 1900 to 1940. Their existence, however, was materially erased from the city and discursively erased from its history after that period. This paper investigates the processes of that erasure, particularly in the American Addition neighborhood of Columbus, concentrating on the articulation of an urban normative that made such land uses appear contrary to "modern" urban development. At the same time, the existence of such practices and landscapes in the city was explained away by a crisis narrative of the garden that helped to support the idea that such practices did not produce "normal" urban spaces. The simultaneous material and discursive colonization of subsistence gardens as "relief" measures during the Great Depression left these landscapes and areas dependent on the City of Columbus, under whose control they were transformed into more "appropriate" cityscapes.  相似文献   

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The medium-sized cities of Brazil are those with populations of between 100,000 and 500,000 inhabitants. These cities are growing rapidly, and are characterized by poor urban planning, a loss of biodiversity and decreasing health prospects for residents. Historically, urbanization in Brazil has been associated with incentives to increase the use of private vehicles for local transport. The air pollution resulting from this “car dependency” has been quantified in some major cities in Brazil, such as the megacity of São Paulo. In this paper, we demonstrate through a bioindication study carried out in the Brazilian city of Rondonópolis, that atmospheric pollution resulting from vehicular emissions is also a measurable reality for medium-sized cities. Most Brazilian cities lack air quality measurement equipment, and we used an inexpensive and easy to apply bioindication assay to measure air pollution, and this approach could be easily implemented in those cities and beyond.  相似文献   

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In this article we explore the relationships between urban form and air pollution among 86 U.S. metropolitan areas. Urban form was quantified using preexisting sprawl indexes and spatial metrics applied to remotely sensed land cover data. Air pollution data included the nonpoint source emission of the ozone (O3) precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs), the concentration of O3, the concentration and nonpoint source emission of fine particulate matter (PM2.5), and the emission of carbon dioxide (CO2) from on-road sources. Metropolitan areas that exhibited higher levels of urban sprawl, or sprawl-like urban morphologies, generally exhibited higher concentrations and emissions of air pollution and CO2 when controlling for population, land area, and climate.  相似文献   

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中国城市舒适物评价指标体系构建与实证   总被引:5,自引:0,他引:5  
马凌  李丽梅  朱竑 《地理学报》2018,73(4):755-770
随着城市经济向新知识经济转型,舒适物被认为是影响高端人才移入和城市经济增长的最重要因素。在西方研究基础上,基于中国国情,探索性地构建了中国舒适物系统的综合指标体系,其中包括自然、文化、商业、交通、卫生和社会等6个一级指标以及34个二级指标。结合中国26个主要人口聚居城市的舒适物指标数据,对不同城市的舒适物综合指数水平进行测评;同时对测评结果的差异进行了解释分析。研究发现:① 城市舒适物综合水平呈现出比较大的差距,北上广深等大城市明显高于中西部城市;进一步聚类分析表明,中国大城市的舒适物水平既存在差异,也存在舒适物发展上的共同特征;② 与西方城市人口普遍重视自然舒适物相反,商业舒适物和交通便利程度是影响中国城市舒适物总体水平的最重要因素,卫生服务设施、文化舒适物、商业舒适物与城市吸引力和宜居程度总体评价的相关性最高,这说明中国目前的经济增长模式仍以物质消费为主,而人才流动主要看重舒适物中的文化和消费设施发达程度、卫生医疗水平和交通便利程度,对自然舒适物和社会舒适物等“软”环境的重视不如西方国家;③ 中国城市舒适物结构呈现出比较复杂的状态,表现为发展不均衡的结构类型。城市舒适物评价指标体系构建紧扣舒适物概念和内涵,具有操作性和延伸性,一方面根据评价结果可以判断中国大城市舒适物水平的优劣与结构特征,另一方面评价结果可用于进一步分析其与城市经济、人才、企业等变量的关系,从而完善中国转型期城市发展和增长理论。  相似文献   

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《Urban geography》2013,34(8):672-690
Our understanding of population loss from U.S. cities draws primarily from the fate of industrial centers in the decades following World War II. Quite numerous, those cities cast off residents at unprecedented and sustained rates. Prior to this time, few large cities had ended a decade smaller in population size than they began. In order to broaden and deepen our knowledge of why some cities and not others lose population, this paper analyzes cities that shed population in the 19th century. Using Census data and capsule stories developed from city biographies, the paper explores both contextuating and precipitating factors. These findings subsequently become the basis for reflecting anew on urban decline since the mid-20th century.  相似文献   

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Jamaica's tourism industry has grown rapidly in recent decades, with significant implications for national development. However, the distribution of the benefits from this growth sector has been socially and spatially uneven. Drawing on substantial data sets collected through a variety of participatory research practices, this paper assesses the socioeconomic and environmental challenges facing the residents of Montego Bay and Falmouth on Jamaica's north coast, the main site for tourism development in the country. The research involved training community residents as researchers, and used traditional quantitative methods alongside techniques borrowed from participatory rapid appraisal.
The local society and economy are clearly shown to be affected by processes of globalization and mobility. However, existing patterns of national economic development – including the expansion of the tourism industry – have failed to alleviate the social and environmental problems faced by relatively powerless members of the Jamaican society. In contrast, the most effective responses to this situation have involved stakeholder groups negotiating and breaking down entrenched scaled relationships through the mobilization of particular forms of social networks.  相似文献   

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Non-profit organizations are key actors in urban and community forestry (UCF) initiatives, and sometimes city residents resist their efforts. Between 2011-2014, 24 percent of residents offered a street tree in Detroit, Michigan, USA submitted a “no-tree request.” Differing views on decision-making emerged as a main reason for resistance to tree planting. This study used interviews with city residents, and those within a non-profit organization, between 2014-2016 to understand reasons for conflict over decision-making between these groups. Heritage narratives, or selective representations of the city’s history and character, helped explain conflict over tree planting. Residents who wanted greater decision-making power in tree planting assumed they would be responsible for stewardship, reflecting their historical experiences within the city. The organization’s dominant heritage narrative emphasized that residents held misperceptions of trees based on negative past experiences, and required education on benefits of trees. Recommendations for integrating heritage narratives into UCF efforts are provided.  相似文献   

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The contingent relation between water governance and nature neoliberalization has defined most interventions in the water sector around the world in recent years. In the case of the Peruvian capital Lima, the provision of water and sanitation services in the last two decades has been the object of investments and institutional reforms strongly influenced by economic neoliberalism. This essay examines the evolution of these neoliberalizing tendencies, noting the internal disputes, necessary adjustments and underlying problems of water sufficiency in the metropolitan region. The empirical results suggest that, rather than a straightforward process, the neoliberalization of water in Lima has advanced according to political opportunities and technico‐operational constraints. The water reforms implemented in the 1990s – when the goal of privatization met political opposition – can be contrasted with the more recent phase in the 2000s, when more flexible mechanisms, such as public‐private partnerships, have facilitated public acceptance. Despite the renovation of the infrastructure, the modernization of the water sector has failed to address persistent water management problems, namely the discriminatory treatment of low income residents, the chaotic expansion of the metropolitan area and the risk of future water shortages.  相似文献   

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Zhigang Li 《Urban geography》2013,34(7):923-949
China's informal settlements—villages inside urbanized areas—are often characterized by local governments as dirty, chaotic, and dangerous places. This negative discourse inevitably leads to recommendations for demolition. A number of criteria have been invoked in state decisions regarding the demolition of informal settlements; however, rarely are these places evaluated from the residents’ perspective. This paper, following a long tradition of residential satisfaction research in Western nations, uses a household survey to examine this topic in the cities of Beijing, Shanghai, and Guangzhou. We find that local contexts not only matter, but may be the principal determinants of residential satisfaction. The residential satisfaction of village dwellers is not necessarily low, and most socioeconomic attributes are not statistically significant determinants of resident satisfaction. Migrants and low-income groups are not less satisfied than nonmigrants or middle-range income earners; the most important determinant is social attachment within the community. The perception of being excluded, or lacking neighborhood social attachment, significantly reduces residential satisfaction. No facilities can compensate for this negative exclusion factor. We conclude that demolishing informal settlements does not help to build a “harmonious society,” which is the purported goal of such programs. Removing the social and institutional barriers for migrant integration into the city is likely the most effective way to enhance residential satisfaction and neighborhood quality.  相似文献   

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基于NASA的全球大气PM2.5年均污染浓度栅格数据,通过对非洲行政边界矢量化、分区统计各国大气PM2.5浓度均值及建立空间数据库,利用重力模型、ESDA模型及GIS空间统计分析方法,对非洲52个主要国家(地区)2001 – 2010年间的大气PM2.5污染浓度时空格局特征演化进行探究,并依据时间序列特征将研究对象划分为8类。研究结果表明:(1)2001-2010年非洲大气PM2.5污染浓度大致呈现“中间高、南北低;西部高、东部低”的空间特征;其中高值区集中分布在非洲西部几内亚湾附近的尼日利亚、刚果与喀麦隆等国家,低值区则广泛地分布在北非、南非以及非洲东南部印度洋沿岸地区或岛屿。(2)基于ESDA模型的空间自相关分析发现PM2.5浓度“高-高”热点区主要集聚在几内亚湾附近主要国家,“低-低”冷点区集中在东南部印度洋沿岸的南非、莫桑比克与马达加斯加岛。(3)时序上2001-2010年非洲PM2.5年平均污染浓度呈现明显下降趋势,其中32个国家(占研究区总数的61.54%)2010年PM2.5污染年均浓度低于2001年。(4)从自然环境条件及社会经济因素两方面浅析其空间格局主要成因:几内亚湾沿岸是非洲PM2.5污染最严重的地区,因其人口稠密且高度依赖石油产业;非洲东南部地区PM2.5污染最轻,得益于其良好的自然环境条件及低污染的支柱产业。  相似文献   

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Since the 1990s, international water sector reforms have centred heavily on economic and market approaches. In regard to water resources management, tradable water rights have been promoted, often supported by the neoliberal model adopted in Chile. Chile's 1981 Water Code was reformed to comprise a system of water rights that could be freely traded with few restrictions. International financial institutions have embraced the Chilean model, claiming that it results in more efficient water use, and potentially fosters social and environmental benefits. However, in Chile the Water Code is deeply contested. It has been criticised for being too permissive and has produced a number of problems in practice. Moreover, attempts to modify it have become the focus of a lengthy polemic debate. This paper employs a political ecology perspective to explore the socio‐environmental outcomes of water management in Chile, drawing on a case study of agriculture in the semi‐arid Norte Chico. The case illustrates how large‐scale farmers exert greater control over water, while peasant farmers have increasingly less access. I argue that these outcomes are facilitated by the mode of water management implemented within the framework of the Water Code. Through this preliminary examination of social equity and the environmental aspects of water resources management in Chile, I suggest that the omission of these issues from the international debates on water rights markets is a cause for concern.  相似文献   

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《Urban geography》2013,34(4):371-376
In the second half of the 20th century, considerable resources and efforts have been devoted to revitalizing American central cities. In these redevelopment processes, however, the common byproduct of physical upgrading is social upgrading, the displacement of many of the original residents, who are often low-income and minority, from their traditional neighborhoods. This article explores the various processes of physical and social upgrading—including locally driven urban renewal, private sector "blockbusting," and gentrification—occurring in late 20th century Houston, Texas. This research also examines the neighborhood characteristics and demographic patterns that influence the occurrence of specific upgrading processes. One location of particular interest in the study is Houston's historic African American community of Freedmen's Town, which has experienced decades of conflict over land and space. Most recently, Freedmen's Town has been at the focus of Houston's urban revival, where physical upgrading has been accompanied by the displacement of the community's traditional population and the destruction of this historic neighborhood.  相似文献   

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