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1.
Exploring the relationships between perceived neighborhood boundaries and street network orientation
The neighborhood is a core unit of analysis in urban research, planning, and policy-making. However, perceptual and historical processes oftentimes result in neighborhoods that are not tied to sub-urban jurisdictions. For instance, historic neighborhoods might lack official spatial definitions, hampering neighborhood-based tasks in local offices. In this case, urban practitioners can benefit from readily available spatial proxies, such as the local street network. In this study, we conducted an exploratory analysis that combines neighborhood mapping and street network modeling. By retrieving participants' sketched boundaries and quantifying spatial orientations of sketched polygons and local network patterns, we were able to measure and compare the relationships between the urban fabric and the perceived extents of two historic neighborhoods in Lisbon, Portugal. The results provided insights for enhancing existing definitions of non-official neighborhoods, outlining new urban districts as well as for discussions about the role of the urban form in shaping people's perceptions. 相似文献
2.
We estimate spatiotemporal models of average neighborhood single family home prices to use in predicting individual property prices. Average home-price variations are explained in terms of changes in average neighborhood house attributes, spatial attributes,
and temporal economic variables. Models adopting three different definitions of neighborhoods are estimated with quarterly
cross-sectional data over the period 2000–2004 from four cities in Southern California. Heteroscedasticity and autocorrelation
problems are detected and adjusted for via a sequential routine. Results of these models suggest that forecasts obtained using
city neighborhood average price equations may have advantage over forecasts obtained using city aggregated price equations.
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3.
《制图学和地理信息科学》2013,40(4):297-316
The purpose of this paper is to identify error properties arising when source maps that individually contain error are added or when the ratio of one map with respect to another is computed. The research approach to the problem combines mathematical analysis and simulation where source maps and error processes have been constructed with specified properties. Geman and Geman's corruption model is used to represent error in individual source maps. The paper reports spatial and aspatial error properties arising from adding and ratioing error-corrupted maps. These are identified as functions of the true characteristics of the individual source maps and the errors inherent within them; the relative contribution of these two components to the errors in maps is quantified by regression (for addition) and ANOVA (for ratioing). The paper considers the broader usefulness of this type of experimental analysis in using artificially constructed maps in geographic information science. 相似文献
4.
Developing a bivariate spatial association measure: An integration of Pearson's r and Moran's I 总被引：1，自引：0，他引：1
Sang-Il Lee 《Journal of Geographical Systems》2001,3(4):369-385
This research is concerned with developing a bivariate spatial association measure or spatial correlation coefficient, which
is intended to capture spatial association among observations in terms of their point-to-point relationships across two spatial
patterns. The need for parameterization of the bivariate spatial dependence is precipitated by the realization that aspatial bivariate association measures, such as Pearson's correlation coefficient,
do not recognize spatial distributional aspects of data sets. This study devises an L statistic by integrating Pearson's r as an aspatial bivariate association measure and Moran's I as a univariate spatial association measure. The concept of a spatial smoothing scalar (SSS) plays a pivotal role in this task.
Received: 07 November 2000 / Accepted: 02 August 2001 相似文献
5.
Residential segregation is a multidimensional phenomenon that encompasses several conceptually distinct aspects of geographical separation between populations. While various indices have been developed as a response to different definitions of segregation, the reliance on such single-figure indices could oversimplify the complex, multidimensional phenomena. In this regard, this paper suggests an alternative graph-based approach that provides more detailed information than simple indices: The concentration profile graphically conveys information about how evenly a population group is distributed over the study region, and the spatial proximity profile depicts the degree of clustering across different threshold levels. These graphs can also be summarized into single numbers for comparative purposes, but the interpretation can be more accurate by inspecting the additional information. To demonstrate the use of these methods, the residential patterns of three major ethnic groups in Auckland, namely Māori, Pacific peoples, and Asians, are examined using the 2006 census data. 相似文献
6.
Measuring segregation: an activity space approach 总被引：3，自引：0，他引：3
While the literature clearly acknowledges that individuals may experience different levels of segregation across their various
socio-geographical spaces, most measures of segregation are intended to be used in the residential space. Using spatially
aggregated data to evaluate segregation in the residential space has been the norm and thus individual’s segregation experiences
in other socio-geographical spaces are often de-emphasized or ignored. This paper attempts to provide a more comprehensive
approach in evaluating segregation beyond the residential space. The entire activity spaces of individuals are taken into
account with individuals serving as the building blocks of the analysis. The measurement principle is based upon the exposure
dimension of segregation. The proposed measure reflects the exposure of individuals of a referenced group in a neighborhood
to the populations of other groups that are found within the activity spaces of individuals in the referenced group. Using
the travel diary data collected from the tri-county area in southeast Florida and the imputed racial–ethnic data, this paper
demonstrates how the proposed segregation measurement approach goes beyond just measuring population distribution patterns
in the residential space and can provide a more comprehensive evaluation of segregation by considering various socio-geographical
spaces. 相似文献
7.
To what degree does the built environment of cities shape the social environment? In this article we use a Schelling‐like agent‐based model to consider how changes to the built environment of cities relate to changes in residential segregation by income and ethnicity. To develop this model we exploit insights from a high resolution historical GIS which maps 100% of the population of Newark, NJ in 1880. Newark in 1880 had a complex social landscape characterized by areas of significant social and economic segregation and areas of relative integration. We develop a Schelling model capable of reproducing these residential patterns. We use this model to explore the decentralization of housing, a specific phenomenon associated with the demise of the walking city in the late 19th century. Holding agent preferences constant, but allowing the landscape of the Schelling model to evolve in ways that reflect historical changes to the built environment, produces changes to the social landscape that are also consistent with history. Our work suggests that changes in residential segregation do not necessarily imply changes to individual attitudes and preferences. Changes in residential segregation can be generated by changes to the built environment, specifically the geographic distribution of housing. 相似文献
8.
Identifying local spatial association in flow data 总被引：5，自引：1，他引：4
In this paper we develop a spatial association statistic for flow data by generalizing the statistic of Getis-Ord, G
i (and G
i
*). This local measure of spatial association, G
ij, is associated with each origin-destination pair. We define spatial weight matrices with different metrics in flow space.
These spatial weight matrices focus on different aspects of local spatial association. We also define measures which control
for generation or attraction nonstationarity. The measures are implemented to examine the spatial association of residuals
from two different models. Using the permutation approach, significance bounds are computed for each statistic. In contrast
to the G
i statistic, the normal approximation is often appropriate, but the statistics are still correlated. Small sample properties
are also briefly discussed.
Received: 18 February 1998/Accepted: 29 September 1998 相似文献
9.
The existing crisis management research mostly reveals the patterns of the public's panic levels from the perspectives of public management, sociology, and psychology, only a few studies have revealed the spatiotemporal characteristics. Therefore, this study investigates the spatial distribution and temporal patterns and influencing factors on the general public's panic levels using the Baidu Index data from a geographic perspective. The results show that: (1) The public's panic levels were significantly correlated with the spatial distance between the epicenter and the region of investigation, and with the number of confirmed cases in different regions when the pandemic began to spread. (2) Based on the spatial distance between the epicenter and the region, the public's panic levels in different regions could be divided into three segments: core segment (0–500 km), buffer segment (500–1300 km), and peripheral segment (>1300 km). The panic levels of different people in the three segments were consistent with the Psychological Typhoon Eye Effect and the Ripple Effect can be detected in the buffer segment. (3) The public's panic levels were strongly correlated with whether the spread of the infectious disease crisis occurred and how long it lasted. It is suggested that crisis information management in the future needs to pay more attention to the spatial division of control measures. The type of crisis information released to the general public should depend on the spatial relationship associated with the place where the crisis breaks out. 相似文献
10.
Mapping fine‐scale urban housing prices by fusing remotely sensed imagery and social media data 
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下载免费PDF全文 The accurate mapping of urban housing prices at a fine scale is essential to policymaking and urban studies, such as adjusting economic factors and determining reasonable levels of residential subsidies. Previous studies focus mainly on housing price analysis at a macro scale, without fine‐scale study due to a lack of available data and effective models. By integrating a convolutional neural network for united mining (UMCNN) and random forest (RF), this study proposes an effective deep‐learning‐based framework for fusing multi‐source geospatial data, including high spatial resolution (HSR) remotely sensed imagery and several types of social media data, and maps urban housing prices at a very fine scale. With the collected housing price data from China's biggest online real estate market, we produced the spatial distribution of housing prices at a spatial resolution of 5 m in Shenzhen, China. By comparing with eight other multi‐source data mining techniques, the UMCNN obtained the highest housing price simulation accuracy (Pearson R = 0.922, OA = 85.82%). The results also demonstrated a complex spatial heterogeneity inside Shenzhen's housing price distribution. In future studies, we will work continuously on housing price policymaking and residential issues by including additional sources of spatial data. 相似文献
11.
针对大范围内住宅建筑图斑自动识别较为困难的问题,该文提出基于决策树模型的分类方法,利用基础测绘中高精度的建筑数据、地理省情监测数据、POI数据、DSM、DEM、腾讯大数据等,以建筑物本身特征和建筑物不同邻域内建筑类型相关因素的空间特征作为决策变量,分别采用QUEST、CHAID、C&RT和C5.0算法构建用于住宅分类识别的决策树模型并进行优选。以济南市(不含原莱芜市)为研究区域进行了实验,结果显示4个模型均未出现过拟合现象,可以用于住宅建筑图斑识别。 相似文献
12.
Spatial optimization for land acquisition problems: A review of models,solution methods,and GIS support 总被引：1，自引：0，他引：1
This article reviews the interdisciplinary research field of spatial optimization for land acquisition problems. We start with a theoretical framework to identify three categories of spatial optimization models: problems with aspatial constraints, location models, and problems with topological constraints. Exact, heuristic, and metaheuristic approaches to solving these problems are critically discussed. Tools that are available in commercial and open‐source GIS packages are reviewed from four aspects. We first survey the off‐the‐shelf support and then the development environments in these packages. A case study of the one‐center problem is used to illustrate the computational performance of different solution methods. Finally the advantages and disadvantages of current GIS data models are discussed. The article concludes with challenges and future directions for solving spatial optimization problems for land acquisition. 相似文献
13.
提出了一种基于居民出行活动特征的个体经济水平推断方法。从出行轨迹的移动性指标、基于居住地的出行特征和出行活动链模式3个方面提取13维出行活动特征，以广州市居民出行日志调查数据为训练和测试数据，利用随机森林方法进行个体经济收入水平的推断与检验。结果表明，该方法能够获得最高80%的个体收入水平推断精度。基于家的出行特征（如工作时间（9:00-18:00）离家距离众数等、出行链模式）以及与出行范围有关的移动性指标（如最大距离、回旋半径）在推断个体经济水平上的重要性较高，而衡量出行地点空间异质性的指标（如空间多样性等）重要性相对较低。 相似文献
14.
在ArcGIS和GeoDA等软件的支持下,本文利用标准差指数、变异系数法,结合重心迁移、空间自相关等探索性空间数据分析法(ESDA),首先,对2000~2014年全国整体农村居民人均纯收入进行时间演变特征分析,接着对2000~2013年全国31个省级农村居民人均纯收入的空间分异格局、重心迁移趋势和空间相关性等特征进行分析。结果表明,中国农村收入增速加快,逐渐超过城镇,贫富差距拉大;中国省级农村居民收入区域分异特征出现变化,由严格的东高西低的梯度型变为中西部较低的局部跳跃型;全局空间正相关性显著,存在空间集聚特征,形成东部沿海省份和东北地区的高值聚集区以及西部大片区域的低值聚集区;从省级收入增长率上来看,区域增速的高低发生转变;农民人均收入重心向西北迁移,有利于减小东西收入差距。 相似文献
15.
Capturing spatial population distribution can offer useful information for urban planning to promote reasonable population distribution and allocate urban resource. Agent-based model (ABM) based on the modeling idea of “bottom-up” can offer the ability to simulate the complex individual behaviors that generate spatial population distribution. Previous ABMs were unable to be extended for simulation of spatial population distribution at a fine scale due to the shortage of fine characterization of the urban environment and the calibration of agents' behavior. This study filled these gaps by proposing a genetic algorithm-ABM (GA–ABM) for fine-scale simulation of spatial population distribution in a manufacturing metropolis. In this model, the employment and residential choice behaviors of agents were defined by the labor economic theory and discrete selection model. Multisource geospatial big data such as enterprise points-of-interest big data and building footprints data were used to finely characterize the labor market and urban environment to reflect the impact of agents' employment choices on their residential decision. Furthermore, the grid-scale population investigation big data were combined with the GA to calibrate the agents' residential decision behaviors. The proposed model was used in Dongguan, the typical manufacturing metropolis in China. As a comparison, the expert-experience-based method-ABM (EEBM–ABM) was also conducted by using the same data set. Through the comparison of the results produced by these two models, it was demonstrated that the model coefficient calibrated by GA could effectively reflect the agents' residential decisions. The calibrated GA–ABM is more capable than EEBM–ABM in simulating spatial population distribution in a manufacturing metropolis. Hence, the proposed model can be used to simulate spatial population distribution in a manufacturing metropolis which helps the urban planner to conduct scientific urban planning. 相似文献
16.
The obesity epidemic and inequalities in access to food are prompting increasing numbers of food environment studies, which rely on secondary data sources for mapping. This article assesses the reliability of the two main food outlet data sources in France: the volunteered geographical information (VGI) collaborative map OpenStreetMap (OSM) and the national business register Sirene. Their information on food outlets was assessed through ground-truthing in the city-region of Montpellier. Sensitivity, positive predictive value, and concordance were computed for each database. We analyzed the socio-spatial variability of these measures according to households' income level. The sensitivity of Sirene is good and that of OSM moderate, while the opposite holds for positive predictive value, and the concordance of both OSM and Sirene is fair. Sirene provides more reliable data on deprived neighborhoods and OSM on wealthy neighborhoods. Caution is recommended regarding the classifications on which they are based, the time required to update the institutional database, and socially influenced contributions to VGI. 相似文献
17.
云南漾弓江流域城乡聚落形态信息提取与分形分析 总被引：7，自引：0，他引：7
利用 1996年 2月和 1999年 11月的TM影像 ,通过对漾弓江流域的遥感影像的光谱特征分析 ,建立地物光谱模型 ,提取区域城乡聚落的时空分布信息。在此基础上 ,根据分形几何理论计算漾弓江流域城乡聚落不同时段空间形态的分形维数 ,从其变化分析流域内聚落空间形态的特征。结果表明 ,欠发达地区城乡聚落空间形态具有分形现象 ,并且城市与农村集镇的分形维数变化不一致 ,1996年丽江地震和 1998年大丽线的开通加速了丽江城和鹤庆城的发展 ,使其形态趋于复杂、不稳定性增大。 相似文献
18.
Inferring the home locations of Twitter users based on the spatiotemporal clustering of Twitter data 下载免费PDF全文
下载免费PDF全文 Residential locations play an important role in understanding the form and function of urban systems. However, it is impossible to release this detailed information publicly, due to the issue of privacy. The rapid development of location‐based services and the prevalence of global position system (GPS)‐equipped devices provide an unprecedented opportunity to infer residential locations from user‐generated geographic information. This article compares different approaches for predicting Twitter users' home locations at a precise point level based on temporal and spatial features extracted from geo‐tagged tweets. Among the three deterministic approaches, the one that estimates the home location for each user by finding the weighted most frequently visited (WMFV) cluster of that user always provides the best performance when compared with the other two methods. The results of a fourth approach, based on the support vector machine (SVM), are severely affected by the threshold value for a cluster to be identified as the home. 相似文献
19.
Although most GIS-based planning support have the capacity to show the location and attributes of different places, very few GIS-based systems are able to describe adequately the degree of spatial interaction, or the geographic accessibility, between places. The Faculty of Geographical Sciences of the Utrecht University (The Netherlands) and the South African Council for Scientific and Industrial Research (CSIR), are developing a methodology to address the problem of measuring accessibility by integrating specialised GIS software (FlowMap) that measures the geographic accessibility between locations within a spatial decision support system (AccessMap). The resulting GIS-tool is applied to the Wild Coast area in South Africa. In this region a lack of accessibility to market centres is perceived as one of the major constraints of economic development in the region. 相似文献
20.
Márcio Poletti Laurini 《Journal of Geographical Systems》2017,19(4):371-398
We propose a spatial error model with continuous random effects based on Matérn covariance functions and apply this model for the analysis of income convergence processes (\(\beta \)-convergence). The use of a model with continuous random effects permits a clearer visualization and interpretation of the spatial dependency patterns, avoids the problems of defining neighborhoods in spatial econometrics models, and allows projecting the spatial effects for every possible location in the continuous space, circumventing the existing aggregations in discrete lattice representations. We apply this model approach to analyze the economic growth of Brazilian municipalities between 1991 and 2010 using unconditional and conditional formulations and a spatiotemporal model of convergence. The results indicate that the estimated spatial random effects are consistent with the existence of income convergence clubs for Brazilian municipalities in this period. 相似文献