Individual Accessibility Revisited: Implications for Geographical Analysis in the Twenty‐first Century

Analytical methods for evaluating accessibility have been based on a spatial logic through which the impedance of distance shapes mobility and urban form through processes of locational and travel decision making. These methods are not suitable for understanding individual experiences because of recent changes in the processes underlying contemporary urbanism and the increasing importance of information and communications technologies (ICTs) in people's daily lives. In this paper we argue that analysis of individual accessibility can no longer ignore the complexities and opportunities brought forth by these changes. Further, we argue that the effect of distance on the spatial structure of contemporary cities and human spatial behavior has become much more complicated than what has been conceived in conventional urban models and concepts of accessibility. We suggest that the methods and measures formulated around the mid‐twentieth century are becoming increasingly inadequate for grappling with the complex relationships among urban form, mobility, and individual accessibility. We consider some new possibilities for modeling individual accessibility and their implications for geographical analysis in the twenty‐first century.     

河南省人口分布与乡镇可达性空间耦合特征

人口作为区域发展的内在因素,交通可达性提高将有利于促进人口或劳动力要素的自由流动和优化配置。在考虑土地利用及地形因素的基础上,采用包含乡村道的交通网络数据集,应用改进的成本距离计算方法,分析河南省乡镇可达性及其分布特征;通过乡镇可达性与人口密度的空间叠加,揭示人口分布与可达性的空间耦合特征。结果表明：①各乡镇可达性总体呈现明显的圈层分布,可达性值由内向外逐渐降低;时段越短,内部差异越大,交通指向越明显。②乡镇可达性与人口密度在各时间圈呈现正相关关系,可达性与人口分布集聚产生作用的最大时间距离为1.5h。③人口与交通可达性的空间耦合呈现较明显的半环状分布,社会经济指向性明显。④交通可达性对人口变化的影响具有时间阶段性和区域差异性。     

The Spatial Association of Demographic and Population Health Characteristics with COVID-19 Prevalence Across Districts in India

In less-developed countries, the lack of granular data limits the researcher's ability to study the spatial interaction of different factors on the COVID-19 pandemic. This study designs a novel database to examine the spatial effects of demographic and population health factors on COVID-19 prevalence across 640 districts in India. The goal is to provide a robust understanding of how spatial associations and the interconnections between places influence disease spread. In addition to the linear Ordinary Least Square regression model, three spatial regression models—Spatial Lag Model, Spatial Error Model, and Geographically Weighted Regression are employed to study and compare the variables explanatory power in shaping geographic variations in the COVID-19 prevalence. We found that the local GWR model is more robust and effective at predicting spatial relationships. The findings indicate that among the demographic factors, a high share of the population living in slums is positively associated with a higher incidence of COVID-19 across districts. The spatial variations in COVID-19 deaths were explained by obesity and high blood sugar, indicating a strong association between pre-existing health conditions and COVID-19 fatalities. The study brings forth the critical factors that expose the poor and vulnerable populations to severe public health risks and highlight the application of geographical analysis vis-a-vis spatial regression models to help explain those associations.     

Rural Accessibility of General Practitioners: the Case of Bruce and Grey Counties, ONTARIO, 1901–1981

Using data from censuses and medical directories and various measures of availability and accessibility, trends in patterns of access at the two-county and township level are considered against the backdrop of substantial changes in the spatial organization of rural areas and in systems of health care delivery. The results suggest that the negative impact of the decline in, and centralization of, general practitioner services available to the dispersed population of the region between 1901 and 1981 was only partly offset by increases in mobility. Individual rural localities fared differently, largely dependent on their location relative to the central place network.
A l'aide de donnkes provenant des recensements, des annuaires medicaux et de d'autres mesures de la disponibilite et de l'accessibilite, nous en venons h considerer, au niveau des deux comtts et des cantons, les types d'accts, tout en gardant en mtmoire les changements importants dans l'organisation spatiale des regions rurales et dans la dispensation des services de santt. Les resultats de notre etude impliquent que I'augmentation de la mobilite a tres peu compenst pour les effets negatifs decline et de la centralisation des services de medecine generale dispensts aux habitants eparpilles de la region entre 1901 et 1981. I1 est evident que le bien-Ctre de chacune des localids rurales a varie grandement et dependait de leur emplacement par rapport au rtseau central.     

COVID-19 in Chihuahua,Mexico: Assessing its spatial behaviour through the inverse distance weighted interpolation technique

This study focused on the spatial evolution of COVID-19 in the state of Chihuahua, Mexico. Data were retrieved from governmental databases and analyzed by means of GIS, applying the inverse distance weighted (IDW) method. The period of December 2019 through November 2021 was split into eight seasons. The root mean square error (RMSE) was used to assess the reliability of the interpolations, showing acceptable values (RSME < 25). During the period, the municipalities of Juarez and Chihuahua reached the highest number of confirmed cases and deaths, Juarez being the main hotspot of contagion (37.2% of confirmed cases; 46.9% of deaths). Four waves of contagion were identified during the evaluated period, with Fall 2020 being the strongest season. Since Fall 2020, the spread of the disease was more often observed in municipalities with the highest human mobility. Although the spread of COVID-19 decreased after Spring 2021, in Fall 2021 records indicated a continuous increase in cases in the state. That could be due to a relaxation of the implementation of sanitary measures, as well as to the propagation of novel COVID-19 variants having an elevated infectious level. Geospatial techniques allowed for an understanding of the spatial spread of COVID-19 and could be useful for its control.     

基于高斯两步移动搜索法的沈阳市就业可达性评价

将高斯两步移动搜索方法引入到就业可达性测度研究中,在证明方法有效性的同时,也对研究案例沈阳市中心城区的就业可达性空间格局、形成机理进行了分析,并提出相应的调控策略。结果显示,沈阳市中心城区的就业可达性在空间上并非均匀分布,而是呈现为明显的中心-外围格局。形成这一格局的机理有:①单中心的城市形态;②城市规划的功能性布局;③居住的郊区化;④旧城改造与政策性住房;⑤地理要素的空间阻隔。提出用足规划手段促进产业与人口均衡化布局、旧城改造与政策性住房的合理落位、完善城市交通,破除路径障碍与培育多中心城市空间结构等调控策略。     

Cities in a pandemic: Evidence from China

This paper studies the impact of urban density, city government efficiency, and medical resources on COVID-19 infection and death outcomes in China. We adopt a simultaneous spatial dynamic panel data model to account for (i) the simultaneity of infection and death outcomes, (ii) the spatial pattern of the transmission, (iii) the intertemporal dynamics of the disease, and (iv) the unobserved city-specific and time-specific effects. We find that, while population density increases the level of infections, government efficiency significantly mitigates the negative impact of urban density. We also find that the availability of medical resources improves public health outcomes conditional on lagged infections. Moreover, there exists significant heterogeneity at different phases of the epidemiological cycle.     

Exploring the associations between cooling centre accessibility and marginalization in Montreal,Toronto, and Vancouver,Canada

Cooling centres provide respite, safety, and social support during extreme heat events for populations that do not have the resources to own or operate in-home air conditioning. The objective of this study was to measure the spatial accessibility of cooling centres and analyze the associations between cooling centre access and marginalization in Montreal, Toronto, and Vancouver, Canada. The potential spatial accessibility of cooling centres within a 15-minute walk was measured at the dissemination area scale using the two-step floating catchment area method. A two-stage modelling approach was used to analyze the associations between cooling centre access and marginalization. Approximately 62%, 58%, and 54% of the populations in Montreal, Toronto, and Vancouver had access to at least one cooling centre. In Montreal and Vancouver, high marginalization areas were more likely to have cooling centre access than low marginalization areas. Of the areas with cooling centre access, smaller access scores were observed in areas with high residential instability. Approximately one-fifth of the areas in each city had no cooling centre access and high marginalization, and may be considered for future cooling centres or programs that improve accessibility to existing centres.     

移动搜索法在教育公共服务可达性评价中的改进与应用——以福州城区幼儿园为例

采用可变步长的两步移动搜索法,以福建省福州市为典型案例,以居民点（普查小区）为分析单元,对各居民点入园空间可达性进行了测算,并与传统的两步移动搜索法进行对比分析,综合判别学前教育资源空间分布特点。研究表明：福州城区入园可达性总体情况并不理想,仅有少数地区、少量人群可以获得较好的幼儿园空间的可达性。入园可达性在地理空间上呈现出多中心结构,高可达性地区主要分布在市中心并在城市周围零星分布,边缘乡镇特别是除西部以外的乡镇地区缺教明显,入园可达性在城区内部差异较大,幼儿园资源过剩地区和稀缺地区呈两极分化的格局。可变步长的两步移动搜索法能更为客观有效地对幼儿园的布局状况进行评价。而传统方法有一定的夸大作用,且降低了内部的差异,在一定程度上掩饰了幼儿园资源分布的不公平现象。     

南京市社区服务设施可达性的空间格局与低收入社区空间剥夺研究

社区服务设施的空间可达性事关城市公共资源分配的社会公平与公正,是反映城市居民生活质量的重要标志。以南京市居住用地作为基本分析单元,对南京市的教育、医疗、商业和公园绿地四大类社区服务设施的空间可达性进行分析;并通过对相关低收入社区的实地调研,研究城市边缘区低收入群体的服务设施空间剥夺问题。研究表明：南京市四类服务设施的可达性水平均呈现出由城市中心区向郊区衰减的空间分异格局;较低的社区服务设施可达性不仅直接造成低收入社区居民对社区服务设施较低的满意度,导致其空间剥夺感的产生,还极大地阻碍着社区归属感的形成,导致社区居民强烈的迁居欲望,在他们较低的支付能力下进一步加剧其空间剥夺感。政府未来在规划面向低收入群体的保障性社区时,更应注重相关服务配套设施建设,做到社会与空间的公正性。     

Geographic accessibility to primary care providers: Comparing rural and urban areas in Southwestern Ontario

This research examines geographical accessibility to primary care providers (PCPs) across urban and rural areas of Southwestern Ontario and examines variations in the distribution of PCPs in relation to the senior population (aged 65 years and older). Information about PCP practices was provided by the HealthForceOntario Marketing and Recruitment Agency. Population data were obtained from the 2016 Census of Canada. To calculate scores for accessibility to PCPs (i.e., PCPs/10,000 population), we applied the enhanced 2-step floating catchment area method with distance decay effect within a global service catchment of 30-minute drive time. A geospatial mapping approach revealed disparities in the distribution of PCPs with a pattern of higher spatial accessibility in or around major urban areas in Southwestern Ontario. Comparative analyses were performed in association with the seniors’ population to identify how accessibility scores were mismatched with the population needs. The outcome of this study will assist researchers and health service planners to better understand the distribution of existing PCPs to address inequalities, particularly in rural areas.     

Reproducible Science Is Vital for a Stronger Evidence Base During the COVID-19 Pandemic

Reproducible research becomes even more imperative as we build the evidence base on SARS-CoV-2 epidemiology, diagnosis, prevention, and treatment. In his study, Paez assessed the reproducibility of COVID-19 research during the pandemic, using a case study of population density. He found that most articles that assess the relationship of population density and COVID-19 outcomes do not publicly share data and code, except for a few, including our paper, which he stated “illustrates the importance of good reproducibility practices”. Paez recreated our analysis using our code and data from the perspective of spatial analysis, and his new model came to a different conclusion. The disparity between our and Paez’s findings, as well as other existing literature on the topic, give greater impetus to the need for further research. As there has been near exponential growth of COVID-19 research across a wide range of scientific disciplines, reproducible science is a vital component to produce reliable, rigorous, and robust evidence on COVID-19, which will be essential to inform clinical practice and policy in order to effectively eliminate the pandemic.     

城市社会区域体系结构公正配置的空间控制原理与路径

从现代人本主义思维出发,以城市社会地理学原理,即从社会空间结构与社区规划角度,探讨城市居民的生活空间的质量构成,体现在城市要满足各阶层居民(社会)生活的空间结构上。而城市(社会)生活的空间结构的健全与否取决于生活空间行为的社区体系与场所体系的空间构成上。主要体现在居民以居住为主的生活行为对立的居舍类型的可获性上。由此,不同阶层居舍类型体系是城市(社会)生活空间质量的区域基础,其空间分布类型的可获性决定对应阶层人群能否获得以居舍为主的生活空间。本文首次从居民选择居住地行为规律以及形成的城市居舍类型空间结构演化的理念下论及城市社会区域空间体系公正配置与空间控制原理。     

城市社区体系结构可获性评价的原理研究

从人本主义的角度出发,以提升城市生活空间质量为目的,运用城市生活空间质量观的理念分析了城市社区体系结构的公正性和客观可获性的内涵。构建了城市社区体系结构可获性评价的模式,即阶层化居舍剥夺指数评价模式和阶层化社会区剥夺指数模式。阐述了基于"城市资源的配置是均等的"这一假设,结合城市社区体系结构可获性评价要素,提出了城市社区体系结构可获性评价的操作模式,以期构建完整的城市社区体系结构,提升城市社会空间的阶层可获性。     

公交站点可达性测度及其在停车分区中的应用

考虑公交与小汽车方式间的可达性差异,提出了依据公交服务水平调控小汽车可达性的停车分区思路,以期实现对小汽车方式的合理限制,支持城市公交优先发展。首先根据居民出行对不同类型公交站点具有不同可达性需求,将以需求点为圆心、站点时空可接近距离为半径的覆盖范围作为基本分析单元,构建基于微观个体时空约束下的公交站点可达性测度模型。其次借助ArcGIS,以昆明市公交网络数据为基础,对站点可达性空间分布特征进行可视化分析,所得结果与城市用地开发整体特征相吻合,验证了模型的合理性。最后以公交可达性水平为主要依据划分停车供给分区,从而对不同分区停车泊位供给的科学配置提供支撑。     

Measuring Accessibility for People with a Disability

This paper discusses some of the inherent problems associated with measuring accessibility for people on a landscape of surfaces, barriers, and travel modes. Along with this discussion we propose a new perspective for measuring accessibility with a focus on people with differing abilities. Even though our focus is on people with a physical disability, such an approach can be easily extended and is able to be generalized to other needs and differences. Traditional measurements of accessibility are flawed, as they fail to directly account for mobility and physical differences among people. They ignore structural barriers and individual mobility limitations that affect travel time, effort, and even successful completion. To make sense of this dilemma, we propose an accessibility measurement framework that includes measures of absolute access, gross access, closest assignment access, single and multiple activity access, probabilistic choice access, and relative access. Most of these measures of access have been proposed by others, but our framework attempts to codify an approach that helps to overcome weaknesses in using only the absolute access measurement currently used in ADA compliance. Such measures can be used to map accessibility as well as to help select the mitigation or renovation projects that yield the greatest increase in accessibility for people with disabilities. We argue that for many urban and building design problems providing absolute access for people with physical disabilities should be accompanied by the use of a relative access measurement, so that removing barriers can be done in the order that provides the greatest improvement in access for a given level of expenditure.     

Primal and Dual Access

Accessibility, measuring the ease of reaching potential destinations, is increasingly being considered as an effective indicator to evaluate the performance of transport and land use interactions. Primal accessibility, a generalization of the first accessibility formulation proposed by Hansen, has been widely used in many studies and demonstrated to be a reliable tool for project, program, and policy evaluation. The dual of accessibility, measuring the time required to reach a given number of opportunities, is less often considered but can be used for optimization in location covering-type problems. This article, hence, clarifies the definitions of primal and dual access, and applies both measures to the Minneapolis—St. Paul metropolitan area for auto and transit to demonstrate their practicality as a metropolitan-level measurement. We explore the correlations and differences between the primal and dual access to better understand the relative strengths of the measures. It is found that, as with primal accessibility, dual accessibility is an efficient approach to evaluate accessibility, which is straightforward to calculate and to explain to policy-makers and the public.     

Spatial-temporal trends in complementary and alternative medicine (CAM) offices in Ontario,Canada

This paper assesses complementary and alternative medicine (CAM) from a spatial-temporal perspective; it would be of particular interest to those who evaluate health care resource accessibility over space. The analysis compares CAM supply (number of offices, employment, and sales) in Ontario by provincial district, metropolitan influence classification, and health care and social assistance employment quintiles using summary statistics, Kruskal-Wallis and median analyses, and local spatial autocorrelation evaluation. Metropolitan areas throughout Ontario, but especially in the southcentral part of the province, are well endowed with CAM supply and tend to be most important in terms of CAM change. CAM offices are increasing in size in the most populated parts of the province and shrinking in regions that are more peripheral. CAM supply per capita is highest in census subdivisions with moderate levels of health care and social assistance employment, a result that is not offset by significant temporal change. While CAM supply is restructuring in many of Ontario's most populated urban locations, the overall attraction of CAM resources to large and small metropolitan areas is clear. If current spatial-temporal trends continue, CAM spatial disparities will be exacerbated as accessibility to CAM in Ontario's most peripheral locations worsen.     

Identifying the Impacts of Land-Use Spatial Patterns on Street-Network Accessibility Using Geospatial Methods

While the land use-street network nexus is well acknowledged, evidence for the one-way impacts of land-use patterns on street accessibility is still inadequate. The measurements of land-use patterns and street accessibility lack systematic knowledge. Their empirical correlations also lack geographical variability, constraining site-specific land-use practices. Therefore, this study overcame the aforementioned limitations by examining the two-level spatial models to formulate accessibility-oriented land plans, using a well-developed Chinese city as an example. Firstly, two landscape metrics—Euclidean Nearest-Neighbor Distance (ENN) and Similarity Index (SIMI)—were used to quantify the intra- and inter-land-use configurations, respectively. Both city-level and local accessibility were measured using spatial design network analysis. Performing both ordinary least squares (OLS) and geographically weighted regression (GWR) models, results identified the statistically significant effects of inter-land-use patterns on two-level street accessibility. An exception was that land-use configurations within residential and industrial regions were irrelevant to street accessibility. We also found GWR was a better-fitting model than OLS when estimating locally-varied accessibility, suggesting hierarchical multiscale land-use planning. Overall, locally heterogeneous evidence in this study can substantialize land use-street network interactions and support the decision-making and implementation of place-specific accessibility-oriented land use.     

A Spatial-Temporal Analysis of Health Care and Mortality Inequalities in China

Two geographers specializing in China TYalyze that country's health care inequality from 1990 to 2008, for the purpose of: (1) examining spatial-temporal variations of health care inequality at multiple scales (the regional, provincial, and county levels); (2) exploring whether economic growth and transition to a market economy have exacerbated the unevenness of health care; and (3) analyzing the impact of health care inequality on health outcomes, especially mortality. The authors apply GIS-based spatial statistical methods to detect spatial-temporal patterns of health care, and use multilevel regression to examine the linkages between health care, mortality, and regional economic inequality, and ultimately to assess the sensitivity of health care inequality to geographic scale and examine whether reforms implemented to date have resulted in more equitable access to health care. The paper also demonstrates how the concurrent transitions of decentralization, marketization, globalization, and urbanization in China have interactively contributed to health care inequality and mortality.