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1.
ABSTRACT. In a polycentric urban context, several urban nodes may exert an influence over land rents. Where this is the case, regression analysis to explain land rents should employ distance variables corresponding to each of the urban nodes. However, these distance measures may be highly intercorrelated, thereby posing a problem of “spatial multicollinearity.” This paper demonstrates that problems arising from spatial multicollinearity can be avoided or substantially lessened by carefully selecting the geographic domain from which observations are drawn.  相似文献   

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The stability of regression coefficients over the observation set (“regional homogeneity”) is typically assessed by means of a Chow test or within a seemingly unrelated regression (SUR) framework. When spatial error autocorrelation is present in cross-sectional equations the traditional tests are no longer applicable. I evaluate this both in formal terms as well as empirically. I introduce a taxonomy of spatial effects in models for structural instability, and discuss its implication for testing. I compare the performance of traditional tests, robust approaches, maximum-likelihood procedures and pretest techniques by means of a series of simple Monte Carlo experiments.  相似文献   

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Contemporary pottery and raw materials (N= 170) from three workshops in Ticul, Yucatán, were analysed by neutron activation to test the hypothesis that individual workshops that used their own clay sources could be identified by their pottery. Although the data failed to confirm the hypothesis, the results reinforced previous conclusions about the relationship of local communities of potters to the chemical patterning of pottery made in these communities.  相似文献   

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ABSTRACT This paper considers the optimal locations of two or more facilities, and the optimal number of facilities, when trips are made in pairs. The results are the same as standard models of spatial competition when there is perfect matching, but not when there is random matching. The first interpretation is bridges across a river, with residential locations on one side matched perfectly or randomly to jobs on the other side. The second interpretation is connecting facilities, such as tennis courts or restaurants where pairs of consumers meet. The third interpretation is product differentiation, with husbands and wives jointly choosing from among varieties.  相似文献   

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M. J. BAXTER 《Archaeometry》2008,50(6):968-982
This review of developments in the use of mathematics and statistics in archaeometry over the past 50 years is partial, personal and ‘broad‐brush’. The view is expressed that it is in the past 30 years or so that the major developments have taken place. The view is also expressed that, with the exception of methods for analysing radiocarbon dates and increased computational power, mathematical and statistical methods that are currently used, and found to be useful in widespread areas of application such as provenance studies, don't differ fundamentally from what was being done 30 years ago.  相似文献   

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This paper offers a reading of Michael Moore's docu-comedy, Roger & Me, a film ostensibly chronicling the director's effort to interrogate General Motors Chairman Roger Smith following massive plant closures in and around Flint, Michigan in the 1980s. Our analysis focuses on four key themes: (1) the status of “community” as an ideological lever both prior and subsequent to GM's layoffs; (2) the spatial consequences of economic restructuring, expressed most formidably in the division between public and private space; (3) the charge that Moore's film suffers from a lack of objectivity; and (4) the notable absence of any significant representation of labor resistance to the plant closures. The film's themes, we argue, coalesce in an emblematic sequence involving Rhonda Britton, a woman who sells rabbits as both pets and meat. The paper concludes by calling for increased attention on the part of geographers to filmic portrayal, and, more generally, to all forms of representation and the issues which surround them.  相似文献   

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ABSTRACT. Total cleared area in a von Thünen land-use model drives an atmosphere externality which depresses agricultural productivity uniformly throughout the region. Exogenous events that encourage clearance and use of a larger cultivated area (output price or population increase) exacerbate the externality. Imposition of a simple, corrective tax on land rents does not reverse these patterns but does mitigate the increase in the externality and leaves cultivators with higher incomes than they would obtain without the tax. We examine an optimal tax on land rents, designed to maximize the social value of land rents in the region, and an output tax.  相似文献   

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An experimental program was conducted to study the inelastic response of steel roof deck diaphragms for low-rise steel buildings subjected to seismic loading. Tests were performed on 3.6 m×6.1 m diaphragm specimens made of corrugated steel deck panels. The parameters examined were the thickness and configuration of the sheet steel panels, the type and spacing of the fasteners, the applied loading history and the influence of end lap joints. Diaphragms built with screwed side lap fasteners and nailed deck-to-frame connectors exhibited a pinched hysteretic behaviour, but could sustain large inelastic deformation cycles with limited strength degradation. This type of diaphragm construction could be designed to resist earthquake effects in the inelastic range. Higher shear resistance and less pinching was observed for systems that included welded with washer connections. However, their strength decreased rapidly after the peak load was reached, and hence, these systems should be designed for limited inelastic response. Deck systems with button punched side laps and frame welds without washers showed a brittle response and should be designed to remain elastic under severe earthquake motions. The inelastic demand was found to increase when the spacing of the fasteners was reduced. Specimens constructed with an internal overlap joint exhibited extensive warping of the cross section mainly due to the shorter panel length.  相似文献   

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ABSTRACT. This paper examines the impacts of JRS articles in the areas of theory, methods and empirical analysis, as represented by subsequent citations reported in the Social Sciences Citation Index. A model relating the mix of theoretical, methodological and empirical research published in the JRS to subsequent citations is estimated. The time distribution of theoretical and empirical citations also indicates that the knowledge diffusion process in these two areas may be segmented.  相似文献   

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The Pichvnari necropolis on the Black Sea coast of Georgia lies in an area known in the late first millennium as ‘Colchis’, on part of the trade route leading to the Orient. The burials of the necropolis date to the late fifth century bc and frequently contain grave goods, including extremely well‐preserved polychrome glass beads and core‐formed vessels. This paper presents a study of these vessels both stylistically and archaeologically and using SEM–WDS and LA–ICPMS. It reveals that the vessels have compositional differences that may point to multiple manufacturing sites. One of the vessels appears stylistically unique and may exhibit one of the earliest uses of manganese as a decolorizer. Major and minor element data for the vessels suggest that they may belong to the same ‘Levantine’ group as many Roman glass objects, suggesting that a source of sand on the coast of the Levant could have been used in their production. The beads clearly show glass with both natron‐ and plant ash‐based flux with distinct rare earth compositions, showing multiple sites of production, some of which were probably either in the Middle East or the Indian subcontinent.  相似文献   

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G. ERAMO 《Archaeometry》2005,47(3):571-592
Seventy‐one oriented specimens from the pre‐industrial reverberatory melting furnace of the Derrière Sairoche glassworks (Swiss Jura) were analysed. During its period of activity (1699–1714), this glassworks produced wood‐ash glass of liquidus temperatures up to 1400°C. Textural and mineralogical features point to temperatures around 1500°C in the melting chamber. The inner structure of the furnace shows chemical contamination due to ash, molten glass and furnace gases. These results reveal the pyrotechnological know‐how of the glassmakers and prove that the thermal performance of this kind of furnace has been under‐evaluated in the past.  相似文献   

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ABSTRACT. We propose a mixed fixed and random coefficients framework for regional modeling. The framework allows the presence of both the region-specific effects and commonality of responses across regions. Bayes solutions for estimating parameters of interest and for generating predictions are derived. Within a Bayesian framework a predictive density approach to evaluate the impact of changes is suggested. We apply the methodology to evaluate the impact of new rate structures on Ontario regional demand for electricity.  相似文献   

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As evidence concerning human mobility during the transition to agriculture in central Europe, we present the results of strontium isotope analysis of human skeletons from the Neolithic village of Vaihingen, Germany. We find significantly more ‘non‐local’87Sr/86Sr values from humans buried in a Neolithic ditch surrounding Vaihingen than from those buried within the settlement. These results fit with previous studies showing a correlation between burial circumstances and strontium isotope signatures from LBK cemeteries of southwestern Germany ( Price et al. 2001 ; Bentley et al. 2002 ). A pilot study of Neolithic animal teeth from Vaihingen suggests that either ‘local’87Sr/86Sr signatures were more variable than the analysed human bones suggest, or that these domestic animals themselves were mobile, perhaps ranged by mobile pastoralists.  相似文献   

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A recent analytical study by SEM–WDS was carried out on 226 glasses from the Late Bronze Age, analysing each of the glasses for a total of at least 22 elements, the largest such analytical study conducted on these glasses. The aim of the analysis was first to identify which elements were brought in with each of the raw materials and, second, to accurately characterize those raw materials. Since different glassmaking sites in Egypt and the Near East would probably use at least some local raw materials and these raw materials will vary slightly from site to site, this has potential for provenancing the glass. Analysis showed new patterns in the compositions of glass from the various sites and led to new conclusions about the supply of raw materials and personnel for the glass workshops. This forms the basis for further work by LA–ICPMS to be presented in part 2 of this paper.  相似文献   

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