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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
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Robert J. Hoard Steven R. Holen Michael D. Glascock Hector Neff J. Michael Elam 《Journal of archaeological science》1992,19(6)
Cryptocrystalline silicates from the Chadron Formation were widely used by prehistoric human groups in the Great Plains of North America. There are two documented quarry areas: Flattop Butte in Colorado and the White River Badlands of South Dakota. Cryptocrystalline silicates from these sources are visually indistinguishable, making it difficult to determine the sources of artefacts found at archaeological sites. In this investigation, neutron activation analysis is used to distinguish the two sources. This technique also identifies lithic material from the Clovis-age Eckles site in Kansas as being from Flattop Butte. 相似文献
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In this article, Louis F. Miron presents a case study of the effects of local ideology and culture on corporate-lead progrowth movements in New Orleans. Miron borrows from critical theory to illustrate how "hegemonic" ideologies such as economic growth may be resisted in local settings. The findings suggest that economic structural relations do not predetermine the course of human agency, and that the success of progrowth movements is contingent upon local cultural conditions and ethos. Through a document analysis of "fiscal reform," a pro-growth ideology advanced by corporate and political elites in New Orleans and throughout Louisiana, the author probes the connections among material conditions, ideology, and the politics of entrepreneurism. 相似文献
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