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ABSTRACT. In this paper some of the most important properties of the behavior of a spatial monopsonist are derived. Many results are mirror images of corresponding results for the spatial monopolist. A few results are, however, genuinely new. A lot of effort is spent in comparing the properties of the profit function under three different pricing policies, f.o.b. (mill)-pricing, uniform delivered pricing, and spatial price discrimination. It is shown, for example, how the profitability and welfare consequences of the different policies are related to the shapes of the supply and demand functions. It is argued that the theory may have important applications in economic analyses of renewable natural resources such as forests, where total transportation costs are nonnegligible.  相似文献   
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This essay examines the role of amateurs in founding the astronomical subdiscipline of astrophysics. During 1840–1870, they initiated many of the observing programs that came to comprise the new specialty. And during 1870–1910, they participated both in the ongoing research of the field and the campaign to provide it with an institutional base. These general trends are illustrated by examples from the lives of ten prominent amateur solar physicists.  相似文献   
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This paper describes the administration procedures of the European Regional Development Fund (ERDF) for Objective 2 in Catalonia. The paper shows also that the flow of an average of 100 million ECU per year from this Fund from 1989–1993, despite having a relatively slight impact on the Catalan GDP, has contributed to solving some of the bottlenecks in the Catalan economy.  相似文献   
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The Greek Neolithic, here divided into five phases, is the oldest in Europe. Geographically, it is the closest to the Near East and has thus long been seen as an impoverished derivative of the latter. However, recent research has tended to emphasize the autochthonous nature of Neolithic development in Europe, including Greece. The Greek Neolithic economy, which was based almost entirely on domesticates, and its densely packed, long-lived villages strongly recall the Near East, as do also the early emphasis on fine, decorated, nonculinary pottery and the wealth of figurines. On the other hand, the evolution of stylistic patterns is specifically Greek, although generally related to trends in the Balkans. Originality in the development of the Greek Neolithic is also seen in its latest phase, with apparent decreases, rather than increases, in site density, social differentiation, and, to some extent, long-distance trade. At the same time, however, the dichotomy became much sharper between the rich agricultural plains of northern Greece and the more pastoral(?) regions of the Peloponnese and Cycladic Islands; this presages similar contrasts during the Bronze Age.  相似文献   
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