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1.
This paper attempts to further the research by Odland and Ellis (1992) in applying event history methodology to the analysis of spatial point patterns (that is, event patterns). Its empirical focus is the event pattern derived from the adoption of an agricultural innovation, the Harvestore, in southern Ontario, Canada, from 1963 to 1986. Event history analysis involves the use of discrete-state, continuous-time stochastic models to investigate a temporal longitudinal record on discrete variables. Event history models are usually concerned with durations of time between events and the effects of intertemporal time dependencies on future event occurrences. As such, they are often referred to as duration models. Many of the methods used in event history analysis allow the use of other nonnegative interval measurements in place of standard temporal intervals to investigate a series of events. In particular, spatial intervals (or durations) of distances between events may also be accommodated by event history models. Our analysis extends the previous research of Odland and Ellis (1992) by using a wider range of parametric models to explore duration dependence, investigating the role of spatial censoring, and using a more extensive set of explanatory variables. In addition, simulation experiments and graphical tests are used to evaluate the empirical event pattern against one generated from Complete Spatial Randomness. Results indicate that the event pattern formed by the Harvestore adopter farms is clustered (that is, is described by positive duration dependency), the sales agent is a significant factor in the distribution of adopters, and that contrasting results are obtained from the analysis using censored data versus uncensored data.  相似文献   

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Local Indicators of Network-Constrained Clusters in Spatial Point Patterns   总被引:3,自引:0,他引:3  
The detection of clustering in a spatial phenomenon of interest is an important issue in spatial pattern analysis. While traditional methods mostly rely on the planar space assumption, many spatial phenomena defy the logic of this assumption. For instance, certain spatial phenomena related to human activities are inherently constrained by a transportation network because of our strong dependence on the transportation system. This article thus introduces an exploratory spatial data analysis method named l ocal i ndicators of n etwork-constrained c luster s (LINCS), for detecting local-scale clustering in a spatial phenomenon that is constrained by a network space. The LINCS method presented here applies to a set of point events distributed over the network space. It is based on the network K -function, which is designed to determine whether an event distribution has a significant clustering tendency with respect to the network space. First, an incremental K -function is developed so as to identify cluster size more explicitly than the original K -function does. Second, to enable identification of cluster locations, a local K -function is derived by decomposing and modifying the original network K -function. The local K -function LINCS, which is referred to as KLINCS, is tested on the distribution of 1997 highway vehicle crashes in the Buffalo, NY area. Also discussed is an adjustment of the KLINCS method for the nonuniformity of the population at risk over the network. As traffic volume can be seen as a surrogate of the population exposed to a risk of vehicle crashes, the spatial distribution of vehicle crashes is examined in relation to that of traffic volumes on the network. The results of the KLINCS analysis are validated through a comparison with priority investigation locations (PILs) designated by the New York State Department of Transportation.  相似文献   

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This paper compares the performances of three exploratory methods for cluster detection in spatial point patterns where the at-risk population is known. After reviewing two existing methods, Openshaw et al. (1987) and Besag and Newell (1991), an alternative method is introduced. These three methods are then compared empirically using two point patterns drawn from a disaggregate housing database consisting of 28,832 observations. Each observation in the data set contains attributes of single-family detached dwellings in the City of Amherst, New York. This paper provides some new insights into the performance of the three methods, as previous applications have used spatially aggregated (and hence rather inaccurate) data. The paper also demonstrates the utility of GIS for this type of spatial analysis.  相似文献   

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Two geographers residing in Beijing discuss the inflows, processing, and consumption of electronic waste—a topic largely neglected in the current literature on globalization. Based on extensive interviews with electronics producers and recyclers in China, the paper explores the global flows of e-waste and concentration of related recycling in coastal China. The authors suggest that recycling activities (authorized as well as illegal) grew in tandem with the dramatic increase in electronics production during the last decade. They note that the country's recycling sector has played a significant role in rural industrialization and local economic development, albeit in conflict with the objectives of environmental protection. Journal of Economic Literature, Classification Numbers: F20, L63, O17, O19. 6 figures, 23 references.  相似文献   

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Models of n2 potential spatial dependencies among n observations spread irregularly over space seem unlikely to yield simple structure. However, the use of the nearest neighbor leads to a very parsimonious eigenstructure of the associated adjacency matrix which results in an extremely simple closed form for the log determinant. In turn, this leads to a closed‐form solution for the maximum likelihood estimates of the spatially autoregressive and mixed regressive spatially autoregressive models. With the closed‐form solution, one can find the neighbors and compute maximum likelihood estimates for 100,000 observations in under one minute. The model has theoretical, pedagogical, diagnostic, modeling, and methodological applications. For example, the model could serve as a more enlightened null hypothesis for geographic data than spatial independence.  相似文献   

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This article aims to demonstrate how the industry characteristics of manufacturing sectors affect the patterns of their spatial agglomeration. It also addresses several intricate issues concerning the measurement of localization economies and estimation of their main determinants in manufacturing industries. The original empirical analysis employs annual industrial data from the Hellenic Statistical Authority (ELSTAT) during the period 1993–2006 in Greece at the prefecture level, i.e. for 51 prefectures. The data processing reveals three important findings. The first is the temporal persistence of localization economies in the Greek manufacturing. The second refers to the high level of agglomeration associated with the high-technology industries as well as the resource- and scale-intensive industries. Lastly, there are significant effects of industry characteristics related to knowledge externalities, labour skills and productivity, scale economies and own-transport expenditure on spatial agglomeration, as resulted from the use of alternative geographic concentration indices and panel data models. Results obtained have implications for policy-makers, who can enhance the regional manufacturing activity by affecting these industry-specific factors. Amongst others, planning measures and policies which aim at promoting the local development and regional convergence should focus on reducing transport costs for firms or sectors, by improving the infrastructure capacity, interconnectivity and quality of services.  相似文献   

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The author, based on field work, interviews, and examination of local and regional literature and official statistical sources, compares the experience in agrarian reform in two disparate locations—KostToma Oblast, northeast of Moscow in the Noncher-nozem Region, and Rostov Oblast on Russia's Black Sea littoral in the fertile Chernozem (Black Earth) region. It examines both the reorganization of state and collective farms and the establishment of private peasant farms in the two oblasts, with particular emphasis on the latter. The sections on private farms represent an initial attempt, based on in-depth information for a limited sample population, to garner insights, at the rayon level, into factors that may be influencing regional variations in the number, size, and location of private farms across the Russian countryside. 2 maps, 6 tables, 53 references.  相似文献   

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本分析东西方思维方式差异对饭店现代化管理的影响,提出外资饭店涌入,人才资源本土化进程中,管理要适合不同的化生态的观点。  相似文献   

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This study proposes a new quadrat method that can be applied to the study of point distributions in a network space. While the conventional planar quadrat method remains one of the most fundamental spatial analytical methods on a two‐dimensional plane, its quadrats are usually identified by regular, square grids. However, assuming that they are observed along a network, points in a single quadrat are not necessarily close to each other in terms of their network distance. Using planar quadrats in such cases may distort the representation of the distribution pattern of points on a network. The network‐based units used in this article, on the other hand, consist of subsets of the actual network, providing more accurate aggregation of the data points along the network. The performance of the network‐based quadrat method is compared with that of the conventional quadrat method through a case study on a point distribution on a network. The χ2 statistic and Moran's I statistic of the two quadrat types indicate that (1) the conventional planar quadrat method tends to overestimate the overall degree of dispersion and (2) the network‐based quadrat method derives a more accurate estimate on the local similarity. The article also performs sensitivity analysis on network and planar quadrats across different scales and with different spatial arrangements, in which the abovementioned statistical tendencies are also confirmed.  相似文献   

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This paper reviews trends over the last two to three decades in the socio‐economic divisions in Australia, focusing on their spatial dimensions. It provides empirical evidence that our society is dividing on multiple dimensions – including shifts in industry and occupational structure, income distribution, the incidence of poverty. And it demonstrates that the differentiations across space in socio‐economic phenomena also have complex multiple dimensions, which are explained inadequately by a ‘city/bush’ dichotomy popularly espoused by politicians and reported in the media. Processes of globalisation, economic restructuring and employment shifts, and changing patterns of population movement are combining to create stark differentials between places both within the major cities as well as in regional Australia. As demonstrated by the recent One Nation phenomenon, voter backlash is strong, and it too has specific spatial characteristics.  相似文献   

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This article discusses Catholic responses to evolution between 1859, the year of publication of Charles Darwin's On the Origin of Species, and 2009, the year in which the scientific world celebrated its 150th anniversary. Firstly, I will discuss how the Vatican initially responded to evolution in the period between 1859 and 1907, the year in which Pope Pius X issued the encyclical Pascendi dominici gregis. Secondly, I will explore the responses of Catholic authorities and intellectuals and identify the local factors that influenced their responses. Also, I will demonstrate that, gradually, Catholics have shifted towards a more lenient position concerning evolution. Thirdly, I will demonstrate that, in the end, the Vatican has complied with this pattern. In general, this article shows that not only Protestants, but Catholics too have struggled to come to terms with evolution and evolutionary theory and that local factors had an impact on these negotiations.  相似文献   

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Experience has recently reemerged as an important analytical category for historians of the Old Regime and the French Revolution. Reacting against the perceived excesses of discourse analysis, which made political language independent of any social determinants, certain post‐revisionists are now seeking to contextualize political language by relating it to the experience of those who use it. Political agency, in these analyses, is understood to be the effect of particular formative experiences. This article suggests that the search for an experiential antidote to discourse is misconceived because it perpetuates an untenable dichotomy between thought and reality. Access to the phenomenon of historical agency should be pursued not through experience or discourse but through the category of consciousness, since the make‐up of the subject’s consciousness determines how he/she engages the world and decides to attempt changing it. After a brief discussion of an important study that exemplifies both the allure and the functionality of the notion of experience, Timothy Tackett’s Becoming a Revolutionary, the article focuses on the evolving political consciousness of a man who became a revolutionary agitator in 1789, J.‐M.‐A. Servan. Analysis of his writings between 1770 and 1789 shows that the way in which his perspective was constructed, rather than the lessons of experience per se, determined the shape of his revolutionary intentions in 1789.  相似文献   

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There is an increasing awareness of the potentials of nonlinear modeling in regional science. This can be explained partly by the recognition of the limitations of conventional equilibrium models in complex situations, and also by the easy availability and accessibility of sophisticated computational techniques. Among the class of nonlinear models, dynamic variants based on, for example, chaos theory stand out as an interesting approach. However, the operational significance of such approaches is still rather limited and a rigorous statistical-econometric treatment of nonlinear dynamic modeling experiments is lacking. Against this background this paper is concerned with a methodological and empirical analysis of a general misspecification test for spatial regression models that is expected to have power against nonlinearity, spatial dependence, and heteroskedasticity. The paper seeks to break new research ground by linking the classical diagnostic tools developed in spatial econometrics to a misspecification test derived directly from chaos theory—the BDS test, developed by Brock, Dechert, and Scheinkman (1987). A spatial variant of the BDS test is introduced and applied in the context of two examples of spatial process models, one of which is concerned with the spatial distribution of regional investments in The Netherlands, the other with spatial crime patterns in Columbus, Ohio.  相似文献   

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