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ABSTRACT. In a simple urban model, where the only spatial distinction made is between center and suburb, we introduce a uniform distribution of preferences for land. Under a logarithmic utility function, we examine how the location and consumption decisions of individuals differ in consequence of their different preferences for land. Comparative statics indicate that the qualitative response of the city at equilibrium to changes in per capita income and transportation cost is not affected by the introduction of such heterogeneity. Possible extensions are also briefly discussed.  相似文献   
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An axiomatic approach to distance is developed which focuses on those behavioral concepts of distance related to movement in space. In particular, spatial movement by behaving units is postulated to involve a choice from among some set of abstract trips in space, and implicitly, to involve the minimization of some relevant notion of trip costs. In this context, the relevant behavioral notion of distance in space is taken to be the minimum-cost distance generated by this choice process. These trip-cost concepts extend the classical notions of paths, path lengths, and shortest paths in metric spaces. Hence many of the analytical results of the paper involve extensions of classical shortest-path distance properties to minimum-cost distances. In addition to these extensions, a characterization theorem is given which specifies the possible functional relationships between trip costs and their associated path lengths. These relationships include most functional forms which are commonly employed in the literature.  相似文献   
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In this paper we analyse a text in Gooniyandi (southern Kimberley, Western Australia), a myth about the acquisition of fire. Our analysis, broadly structuralist-functionalist in orientation, uses a number of complementary modes of myth analysis, including a variety of structuralism which draws on Lévi-Strauss. Our main point, however, differs from his concerns. It is that the analysis of a myth (indeed, of any text) cannot be pursued independently of its language, and of the linguistic choices implemented by the narrator. Relevant choices include not just lexical, but also grammatical ones, selections of grammatical construction (and patterns in them), not, of course, in the language of translation (English), but in the language of the text. We suggest that our method should be generally applicable to myths in any language.  相似文献   
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In 1985 a Neanderthal skeleton was found in the cave of Kebara in southern Mt. Carmel. Electron spin resonance (ESR) dates have been obtained on tooth enamel of gazelles found in layer X, just overlying the layer in which the skeleton was found. Assuming early uptake of uranium by the teeth, they yield an age of 60 ± 6 ka; assuming gradual, linear uptake of uranium yields an age of 64 ± 6 ka. Both age estimates are consistent with a previous estimate for the skeleton, based on TL dating of burnt flint, of 60 ± 4 ka.  相似文献   
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