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ABSTRACT. We reexamine the price structures and their welfare implications in three pricing regimes (mill, uniform and discriminatory) for a monopoly. We show that spatial price discrimination could provide the highest social welfare and, when consumers tastes are heterogeneous enough, also the highest consumer surplus. The superiority of spatial price discrimination is partially due to the larger output produced and partially due to differential treatment for consumers with heterogeneous tastes. 相似文献
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R. Burleigh Juliet Clutton-Brock P. J. Felder G. de G. Sieveking 《Journal of archaeological science》1977,4(4):353-366
The complete skull and skeleton of a dog were recently excavated from the neolithic flint mines at Grime's Graves in Norfolk. As very few complete skeletons of dogs have been found from neolithic contexts in Britain a detailed metrical comparison was made between the Grime's Graves specimen and dog skeletons of comparable antiquity and completeness from Easton Down and Windmill Hill in Wiltshire.Implicit in the study of the dog from Grime's Graves was the need to date it precisely. As the skeleton could not be sacrificed for radiocarbon dating, closely associated antlers of Red deer (Cervus elaphus) were used for this purpose. The date of the Grime's Graves dog is compared with the dates for other dog remains from recently excavated neolithic sites in the British Isles. 相似文献
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Rafael M. Martínez Sánchez Juan Carlos Vera Rodríguez Leonor Peña-Chocarro Youssef Bokbot Guillem Pérez Jordà Salvador Pardo-Gordó 《African Archaeological Review》2018,35(3):417-442
The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area. 相似文献