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1.
Constructing the Spatial Weights Matrix Using a Local Statistic 总被引:3,自引:0,他引:3
Spatial weights matrices are necessary elements in most regression models where a representation of spatial structure is needed. We construct a spatial weights matrix, W , based on the principle that spatial structure should be considered in a two‐part framework, those units that evoke a distance effect, and those that do not. Our two‐variable local statistics model (LSM) is based on the Gi* local statistic. The local statistic concept depends on the designation of a critical distance, dc, defined as the distance beyond which no discernible increase in clustering of high or low values exists. In a series of simulation experiments LSM is compared to well‐known spatial weights matrix specifications—two different contiguity configurations, three different inverse distance formulations, and three semi‐variance models. The simulation experiments are carried out on a random spatial pattern and two types of spatial clustering patterns. The LSM performed best according to the Akaike Information Criterion, a spatial autoregressive coefficient evaluation, and Moran's I tests on residuals. The flexibility inherent in the LSM allows for its favorable performance when compared to the rigidity of the global models. 相似文献
2.
Jie Lin 《Geographical analysis》2020,52(2):190-210
Local analysis can provide specific information about individual observations that is often useful in understanding nonstationary interactions among variables. This paper extends the application of Wartenberg’s Multivariate Spatial Correlation (MSC) method to a local setting. The original MSC can be considered as an adaptation of Principal Component Analysis for spatial effects with respect to spatial autocorrelation. The extended MSC method described in this paper, however, further incorporates another spatial effect, spatial heterogeneity, by the addition of geographic weights in standardizing the data and in calculating the spatial association weight matrix. The extension allows more local analysis and facilitates additional visualization of the results. The geographically weighted MSC is illustrated and justified using the classic dataset collected by André-Michel Guerry on moral statistics in 1830s France. 相似文献
3.
旅游吸引物空间结构分析——以中国首批国家4A级旅游区(点)为例 总被引:54,自引:0,他引:54
本文利用地理数学方法中的空间分析手段,通过对首批国家4A级旅游区(点)在不同地域范围的空间分布规律进行研究,以及对各旅游区(点)与非农业人口在20万以上的城市之间的空间关系分析,揭示了国家首批4A级旅游区(点)的空间结构整体特征,以及与不同规模客源市场之间的距离分异特征,为旅游目的地空间结构理论研究提供了基础方法。 相似文献
4.
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. 相似文献
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John Modell 《Historical methods》2013,46(1):32-36
Abstract The geographic perspective on human behavior emphasizes the notion of context. Context suggests that human behavior is partly determined by the place in which individuals and groups act, and in turn these actions re-create places. It follows that an element of history is the contextual setting of activity. Spatial statistics are introduced as a tool for modeling context in historical studies. Spatial dependence serves to operationalize the specificity of place and the diffusion of processes between places. Spatial heterogeneity serves to operationalize the idea that behavior is regionally specific rather than uniform across space. Both spatial dependence and spatial heterogeneity are included in spatial regression models. A spatial statistical analysis of the Nazi Party vote in Bavaria between 1928 and 1932 is adopted to illustrate the argument. 相似文献
7.
AbstractSpatial proximity is credited with numerous virtues in the economic literature. In particular, for a company to be located near other companies is seen as conducive to the development of business relations. Spatial proximity is also considered to contribute to the quality and efficiency of these relations by facilitating face-to-face meetings that foster the exchange of complex knowledge and, in particular, the emergence of innovation. This article explores the notion of spatial proximity in intercompany relations, its capacity to facilitate exchange, as well as the link with the methods of communication employed (information and communication technologies and face-to-face). It is based on a distinction between real proximity (the spatial distance between firms), perceived proximity (the spatial distance as evaluated by the firm itself) and active proximity (spatial proximity that facilitates the exchanges). The data come from a survey conducted in 2008 with more than 2000 firms located in the Brittany region (France). The findings emphasize the relative nature of the notion of spatial proximity and the distinction in some cases between real and active proximities, and show that the positive perception of the role of spatial proximity is sustained by the increased face-to-face contact it entails. 相似文献
8.
Sang-Il Lee 《Geographical analysis》2009,41(2):221-248
This article establishes a unified randomization significance testing framework upon which various local measures of spatial association are commonly predicated. The generalized randomization approach presented is composed of two testing procedures, the extended Mantel test and the generalized vector randomization test. These two procedures employ different randomization assumptions, namely total and conditional randomization, according to the way in which they incorporate local measures. By properly specifying necessary matrices and vectors for a particular local measure of spatial association under a particular randomization assumption, the generalized randomization approach as a whole yields a reliable set of equations for expected values and variances, which then is confirmed by a Monte Carlo simulation utilizing random permutations. 相似文献
9.
Spatial Dynamics of Local Labour Markets in the Québec City Metropolitan Field, 1981–2001
This research analyzes the spatial dynamics (from 1981 to 2001) of local labour markets at an infra-regional scale, namely the Québec metropolitan field, with particular emphasis on interactions between the metropolitan region and its hinterland. It seeks to better understand the factors underlying this evolution. Centrographic analyses were performed to characterize the evolution of the spatial configuration of local labour markets (displacement of gravity centre, shape change, evolution of dispersion indices and of workforce preferential distribution axes). Between 1981 and 2001, almost all employment poles experienced an increase in the mean-distance tied to their recruitment area, that being particularly true for peri-metropolitan poles which employ an increasing part of their workforce inside the metropolitan labour basin, where a more qualified and diversified labour force is available; thus, giving rise to significant reverse commuting. In addition to the influence of distance to metropolitan area, a multiple regression model shows that factors such as manufacturing specialization and employment growth within job centres also play a crucial role in the spatial dynamics of local labour markets in the Québec City metropolitan field. 相似文献
This research analyzes the spatial dynamics (from 1981 to 2001) of local labour markets at an infra-regional scale, namely the Québec metropolitan field, with particular emphasis on interactions between the metropolitan region and its hinterland. It seeks to better understand the factors underlying this evolution. Centrographic analyses were performed to characterize the evolution of the spatial configuration of local labour markets (displacement of gravity centre, shape change, evolution of dispersion indices and of workforce preferential distribution axes). Between 1981 and 2001, almost all employment poles experienced an increase in the mean-distance tied to their recruitment area, that being particularly true for peri-metropolitan poles which employ an increasing part of their workforce inside the metropolitan labour basin, where a more qualified and diversified labour force is available; thus, giving rise to significant reverse commuting. In addition to the influence of distance to metropolitan area, a multiple regression model shows that factors such as manufacturing specialization and employment growth within job centres also play a crucial role in the spatial dynamics of local labour markets in the Québec City metropolitan field. 相似文献
10.
The Analysis of Spatial Association by Use of Distance Statistics 总被引:20,自引:0,他引:20
Introduced in this paper is a family of statistics, G, that can be used as a measure of spatial association in a number of circumstances. The basic statistic is derived, its properties are identified, and its advantages explained. Several of the G statistics make it possible to evaluate the spatial association of a variable within a specified distance of a single point. A comparison is made between a general G statistic and Moran's I for similar hypothetical and empirical conditions. The empirical work includes studies of sudden infant death syndrome by county in North Carolina and dwelling unit prices in metropolitan San Diego by zip-code districts. Results indicate that G statistics should be used in conjunction with I in order to identify characteristics of patterns not revealed by the I statistic alone and, specifically, the Gi and Gi* statistics enable us to detect local “pockets” of dependence that may not show up when using global statistics. 相似文献
11.
Franois Bavaud 《Geographical analysis》1998,30(2):153-171
General properties of spatial weights models, in particular Markovian properties, are systematically investigated. The role of stationary spatial distribution, interpretable as an importance-centrality or prominence index, is emphasized. Spatial interaction models, and among them the gravity model, are classified with respect to the time reversal and aggregation invariance properties obeyed by the associated spatial weights. Nine examples, involving connectivity, flows and distance decay analysis, integral geometry, and Dirichlet-Voronoi tessellations illustrate the main concepts, with a particular geometrical emphasis, and show how traditional, heuristic ingredients aimed at defining spatial weights can be recovered from general models. 相似文献
12.
基于可达性与场强模型的中国地级以上城市空间场能测度 总被引:2,自引:0,他引:2
空间场能是区域中心城市借助区域联系通道带动腹地发展而产生的"势能差"的抽象表达,可有效刻画区域发展格局与空间差异。采用主成分分析法与指标体系计算城市结节性指数,借助ArcGIS软件平台,采用累积耗费距离法、K阶数据场和ESDA等方法,综合测度了中国287个地级以上城市可达性与空间场能,并分别从省域、市域、县域等单元探讨了中国东中西三大地带与南北场能差异的空间格局与演变特征。结果表明:中国地级以上城市的可达性条件不断改善,平均可达性时间从1991年的246.98min缩短为2010年的193.43min。空间场能显著增长且空间分异性显著,分布结构由单核向多极网络状形态转变。县域场能存在显著的空间极化现象,场能热点区域的分布呈现显著的热点-次热点-次冷点-冷点自东向西带状分布的格局。依据场能分析结果,将全国划分为3个一级经济区和26个二级城市经济区。 相似文献
13.
Roberta Capello 《European Planning Studies》2009,17(5):639-658
Spatial spillover effects are widely studied in the literature, as an important source of externality and therefore of discrepancy between private and social optimum, creating the emergence for ad-hoc policy interventions. Within the literature, their spatially-bounded nature is highly emphasised, but the mechanisms for their spatial diffusion are generally considered as a black box, with no reference to territorialized channels through which these externalities spread around. The study aims to present a literature review on the spatial spillover concept, emphasising two main stages of reflection, the so-called spatial approach and the functional approach. This work identifies in a third approach, the cognitive approach, a new perspective to the interpretation of spatial spillovers and their conditions, and on this approach it elaborates theoretically and empirically. The main assumption is that the capabilities of economic agents to absorb and utilize spillovers—implicitly assumed by the spatial spillover theory to be invariant with respect to space—in reality highly depend on strongly territorialized and un-imitable assets, such as local trust, sense of belonging and creativity. This assumption is tested empirically on all NUTS 2 of the 27 European member countries, thanks to a regional forecasting growth model developed by the author, called MASST. 相似文献
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Impact of Polycentric Urban Systems on Intra-regional Disparities: A Micro-regional Approach 总被引:1,自引:0,他引:1
Jiří Malý 《European Planning Studies》2016,24(1):116-138
From the normative perspective of EU regional policy, polycentric spatial development has been seen as an effective tool to overcome regional disparities since the adoption of the European Spatial Development Perspective. However, the impact of a polycentric spatial structure on equal spatial development is ambiguous and still waits for its clarification. This paper examines the relationship by focusing on the local scale, where medium-sized towns play a crucial role as local centres in everyday human lives. Using functional regions of the Czech Republic, this paper defines polycentric urban systems at the micro-regional scale. Subsequently, the level of mono/polycentricity is compared with intra-regional disparities. Based on the results of the analysis, it can be argued that the connection of polycentricity with balanced spatial development is strongly determined by selected indicators. However, the findings do not provide evidence about the strictly positive impact of polycentricity on intra-regional disparities. In a light of these results, the conclusion is rather sceptical about the unique role of polycentricity in spatial development and due to the lack of similar studies, further research is recommended. 相似文献
16.
Testing for Local Spatial Autocorrelation in the Presence of Global Autocorrelation 总被引:22,自引:0,他引:22
A fundamental concern of spatial analysts is to find patterns in spatial data that lead to the identification of spatial autocorrelation or association. Further, they seek to identify peculiarities in the data set that signify that something out of the ordinary has occurred in one or more regions. In this paper we provide a statistic that tests for local spatial autocorrelation in the presence of the global autocorrelation that is characteristic of heterogeneous spatial data. After identifying the structure of global autocorrelation, we introduce a new measure that may be used to test for local structure. This new statistic Oi is asymptotically normally distributed and allows for straightforward tests of hypotheses. We provide several numerical examples that illustrate the performance of this statistic and compare it with another measure that does not account for global structure. 相似文献
17.
Kate Pangbourne 《European Planning Studies》2015,23(3):494-508
Agricultural policy and farm lobby groups often stress the role of farm production in sustaining local economies. This paper considers the spatial pattern of upstream and downstream agricultural transactions of farms in North East Scotland and, in particular, the extent to which they take place within the locality of the farm holding. Three alternative definitions of “local” are considered: a distance-based measure; a measure which takes into account the location of the farm in relation to the nearest town; and a measure which takes into account the location of agribusinesses, defining a transaction as local if the farmer buys from (sells to) the nearest available input supplier (output purchaser). The results highlight the importance of allowing for context when explaining farmer purchasing and sales decisions. They also reveal a highly complex pattern of production-related linkages in the region, with many farmers choosing to bypass their most proximate agribusinesses. Certain towns are found to dominate agriculture-related transactions in the region, reflecting the spatial concentration of upstream and downstream agribusinesses. The findings provide new insights into theoretical debates on the role of small towns in the urban system and the changing importance of geographical distance in determining business transactions. 相似文献
18.
Due to a change in capital funding formula, many school boards across the Province of Ontario engaged in Accommodation Reviews to rationalize the supply of school capacity. This process led to numerous school closures and raised important policy questions regarding the economic value of a school in terms of its capitalization into property values and, by extension, how the closure of a school might affect local neighborhoods. To explore these questions, this research uses spatial hedonic methods to estimate the implicit value of accessibility to schools in the City of Hamilton, Ontario. Spatial Durbin model results provide evidence of a significant negative correlation between distance to schools and housing prices in the Canadian context. This suggests that accessibility to schools is capitalized into property values and that the closure of a neighborhood school may result in potentially significant losses of economic value in communities. 相似文献
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This note presents a new measure of spatial imbalance that uses the center of gravity (or the mean center) of a distribution and the geometric center (or the centroid) of a region to define a vector indicating the relative position of the distribution in the region. The spatial imbalance of a distribution in a region is defined as the distance and directional deviation of the center of gravity of the distribution from the geometric center of the region. The convex hull of a region is introduced as the reference for maximum spatial imbalance of the distribution in the region. The spatial imbalance is measured in terms of (1) the relative distance of the center of gravity between the geometric center and the convex hull; and (2) the direction from the geometric center to the center of gravity. This new measure is tested by quantifying the westward movement of the contiguous U.S. population between 1790 and 1950. It describes the well‐known observation that the U.S. population was moving westward across the contiguous United States and toward reduced spatial imbalance. 相似文献