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This paper examines the theoretical implications of quantity-discounted transportation rates on the optimum location decision of the firm. It shows that the linearly homogeneous or homothetic production function is not a sufficient condition for the independence between the optimum location and the output level, unless (i) the elasticities of transportation rates with respect to quantity shipped are constant and identical, and (ii) the ratios of marginal products 60 the marginal transportation costs are equal for each input.  相似文献   
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The late Stone Age Pitted Ware site at Ajvide, Gotland, in the Baltic Sea, Sweden, has revealed a large deposit of fishbone and approximately 400 bone fishhooks, complete and incomplete. Cod (Gadus morhua), which is one of the most abundant fish species in the bone assemblage, was probably caught with hook and line fishing. To investigate the fishhooks' field of application, a morphological and morphometric study was performed on 384 available hooks. Two sets of replicas made of four selected original fishhooks were submitted to a strength test. A breakage study of the incomplete hooks in comparison with the strength-tested hooks was carried out in order to distinguish fresh breaks from dry breaks. It seems that a certain morphology for fishhooks was preferred at Ajvide, indicating they were produced by skilled craftsmen for special usage. The strength test showed that the hooks had a weight bearing capacity more than the average size of cod caught at Ajvide. Using results of these tests, we predicted that the mean breaking strength of 46 intact Ajvide hooks was 96.6 ± 26.1 (s.d.) Newtons (equivalent to 9.85 ± 2.7 kg). The design of fishhooks changed somewhat over time, being slightly larger in the oldest layers of the site. The breakage patterns of the hooks show that the bow was the most common area of breakage. The design and weight bearing capacity of the hooks point to a specialized cod fishery from boats in deep water.  相似文献   
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