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ABSTRACT. This paper uses a two-stage hedonic wage approach to derive the benefits from improvement of five cultural amenities. It is argued that the hedonic approach permits valuation of both private and local public aspects of cultural goods since access to the amenity is an essential input in the production of the final service flow. Empirical estimates of willingness to pay suggest price and income elasticities are approximately unity. Lower-bound estimates of marginal benefits for a representative city range from $0.85 million for an additional theater to $57.9 million for an additional zoo facility. 相似文献
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ABSTRACT The origins and development of the network equilibrium problem are traced and interrelated. Two principal formulations are considered the network equilibrium problem with variable travel demand, and the combined model of trip distribution and traffic assignment. The relation of these models to subsequent developments concerning mode choice, residential location, estimation of origin-destination tables from link flows and stochastic route choice are then reviewed. 相似文献
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David J. Meltzer 《Journal of World Prehistory》1988,2(1):1-52
Eastern North America in late Pleistocene times was characterized by two major environmental regions: a periglacial tundra or open spruce parkland and an extensive complex boreal/deciduous forest in the unglaciated, lower latitudes. These environments selected for different adaptive strategies on the part of human foraging groups—known archaeologically as Paleoindians. Those in the tundra and tundra-forest region were highly mobile, possibly specialized hunters, exploiting caribou; those in the forest were generalists, exploiting a variety of subsistence resources with a less mobile settlement system. There is little evidence in either area for hunting of Pleistocene megafauna. These differences in adaptive strategies are reflected in the record of sites and isolated fluted points scattered throughout the region, as well as aspects of tool technology, function, and patterns of stone use. 相似文献
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Helene Roche Jean-Philippe Brugal David Lefevre Sylvie Ploux Pierre-Jean Texier 《African Archaeological Review》1988,6(1):27-55
Résumé Isenya est le premier site acheuléen fouillé sur les hauts plateaux du Kenya. Sa richesse en vestiges lithiques et fauniques en fait dès maintenant un gisement important pour la connaissance des hominidés du Pléistocène moyen. Isenya est inclus dans un contexte sédimentaire fluviatile, indiquant que les hommes préhistoriques se sont installés sur une barre sableuse, le long d'une rivière qui était alors peut-être pérenne. La convergence des informations géologiques et archéologiques permet d'expliquer la mise en place des vestiges, la positionin situ de plusieurs niveaux d'occupation superposés, le faible degré de perturbation qu'ils ont subi, et l'origine essentiellement anthropique des associations os/pierres. L'industrie lithique est caractérisée par une grande abondance de bifaces et de hachereaux dont les proportions varient dans le temps. Une première analyse de l'ensemble apporte d'ores et déjà des indications sur les comportements techniques: les chaînes opératoires sont décryptées, depuis l'acquisition des matériaux jusqu'à l'obtention des outils. La faune associée à cet outillage est dominée par des animaux de savane ouverte (Alcelaphini etAntilopini). Son étude détaillée mettra en évidence les stratégies d'acquisition du gibier et son mode de consommation. Attirés, entre autres raisons, par la proximité de l'eau et des affleurements de phonolite, source principale de matière première pour l'outillage, les hominidés ont occupé cet enfroit de façon répétée dans un court laps de temps, selon une périodicité à rapprocher sans doute des comportements de subsistance.
Isenya is the first Acheulian site excavated in the Eastern Highlands of Kenya. Very rich lithic and faunal remains in a fluviatile sedimentary context indicate hominid activity on a sandy bar next to a river, which was perhaps perennial. Microstratigraphy and archaeological data permit reconstruction of the processes by which the remains were deposited. Severalin situ occupation layers show only a slight degree of perturbation. The bone assemblage is of anthropic origin, and the lithic industry is characterized by an abundance of bifacial pieces, level VI being particularly rich in cleavers. From the analysis of the lithic industry we can obtain some idea of hominid technological behaviour, most notably the operational chains of tool production from the procurement of raw materials to the knapping sequences. The fauna associated with the lithic materials is dominated by animals of the open savanna (Alcelaphini andAntilopini); and its detailed study will allow us to specify the strategies used in the procurement of game and its subsequent consumption. Without doubt, the reasons for hominid occupation at this particular site will be impossible to explain fully. However, choice of this location, where evidence for several different activities has been uncovered, should be considered in terms of the proximity both of water and of outcrops of phonolite, the principal raw material for tool-making. Repeated occupation by hominids over a short time may, perhaps, correspond to the periodicity of their subsistence behaviour.相似文献
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