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《Southeastern Archaeology》2013,32(2):242-267
Abstract

Freshwater mussel shell was used as a temper in the manufacture of ceramic vessels by potters in the Caddo area of the southeastern United States after ca. A.D. 1300. This was at least one or two centuries after it became the dominant temper used by aboriginal groups in much of the Eastern Woodlands but generally contemporaneous with shelltempered usage in parts of the Southern Plains. The introduction of shell temper was variable across the Caddo area, and in certain regions its use was negligible in ceramic vessel assemblages until the sixteenth and seventeenth centuries but then was rapidly adopted as the dominant temper employed in vessel manufacture, particularly for utility wares. In the traditional territory of the historic Hasinai Caddo in East Texas, shell temper did not appear in vessels until the early eighteenth century, and then only in minor amounts on presumed trade vessels.  相似文献   

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ABSTRACT. This paper applies the production-theory approach to assess the impact on domestic wages and employment of immigration to the United States. Inputs are disaggregated between recent immigrants, non-recent immigrants, native workers, and capital. Census cross-sectional data for 1980 and for 123 metropolitan areas are used. Empirical estimates are reported for alternative functional forms with special attention devoted to required curvature conditions which have frequently been violated in previous work. Elasticity estimates are reported for alternative settings, including for the short run where we view domestic factor prices as given and the long run where we treat them as flexible.  相似文献   

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ABSTRACT.  This study estimates a series of random parameter logit models of the college-to-work migration decisions of technology graduates and holders of doctorates within the United States. We employ detailed information on the migration-relevant characteristics of individuals, as well as on their actual origins and destinations at the metropolitan scale. In addition to its obvious implications for "brain drain" policies in U.S. metropolitan areas, the study demonstrates the richness of the random parameters technique for behavioral-geographic analysis. We find that science and technology graduates migrate to better educated places, other things equal; that PhD graduates pay greater attention to amenity characteristics than other degree holders; and that foreign students from some immigrant groups migrate to places where those groups are concentrated.  相似文献   

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美国绿色空间理论、实践及启示   总被引:2,自引:0,他引:2  
本文介绍了绿色开敞空间概念,研究了美国城市公园系统、区域整体、绿道、自然风景、景观生态规划、大地景观、纽约城乡规划设想等重要理论,概述了其绿色空间发展历程,分析了美国自然风景园、公园运动、国家公园、开放空间规划、绿道等实践。最后,从自然风景名胜区体系、绿色空间区域生态化、绿色空间自然化、绿道网络化、园林创新、绿色开放系统等方面探讨了美国绿色空间理论与实践对我国的重要借鉴和启示。  相似文献   

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ABSTRACT. Responding to continuing discussions in this Journal regarding the importance of regional money supply and credit, a simple reduced-form regional money supply model is posited and an investigation of real regional money supplies is performed for several states around the country. Hypothesis tests are performed regarding the question of regional financial market segmentation, concluding that segmentation still exists in the United States. The empirical results also imply that interregional trade, presumably via the consequent constraint on regional banks, has at least as much effect on regional money supplies as Federal Reserve policies. These results lend further support for the assertion that regionally available money matters at the local level, and that regional analysis should continue to include regional money and credit as explanatory variables. The implications for policy makers are that: 1) national monetary policy cannot cure regional ills if the problems are manifested in regional industry mixes; and 2) some proposed banking reforms now being debated in Congress, i.e, nationwide branch banking and, particularly, industrial ownership of banks, are suspect. A healthy caution is warranted without more tests of these reforms.  相似文献   

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This paper advances the spatial-choice modelling literature by further examining the way in which spatial knowledge is gained. The specific research purpose of this paper is to see how a major boundary (the U.S.A.-Canada border) will affect the generation of a spatial-knowledge surface. It is accepted that an important impact on the way an individual makes a spatial choice, such as a decision to migrate, is the amount and quality of the information he / she possesses about different locations. A positive influence on such a knowledge surface is the population size of the location. Negative influences include the separating distance between individual and location, and the degree of clustering the location faces in respect to other places around it. This paper investigates the way in which these influences also hold if a major boundary lies between a subject and the investigated research space. The paper uses a multi-variate model calibrated on lists of recalled United States city names generated at 9 different Canadian test sites. These are then compared to similar model results from 22 U.S. test sites. The Canadian test results are more consistent than those for the United States. Also, for Canadian subjects, there is no distance decay in the probability of recalling a location unless the Canadian test site is located proximate to a major American border city. A strong relationship exists between the population size of the recalled location and its probability of being recalled. There is also further evidence to support a hierarchical method of knowledge processing, albeit in a weaker form than found in the U.S. test sites. Cet article contribue à la documentation sur la modélisation des choix spatiaux en analysant comment on acquiert des connaissances sur l'espace. Le but spécifique de la recherche est d'observer comment une frontière géographique (la frontière entre les États-Unis et le Canada) influencerait la génération d'une surface de connaissances spatiales. Lorsqu'un individu choisit un lieu d'une perspective spatiale (et lorsqu'on prend une décision de migrer) la quantité et la qualité des ren-seignements qu'on possède au sujet des différentes situations influencent profondément sa décision. La population d'un lieu a une influence positive sur une telle surface de connaissances. Parmi les influences négatives il y a la distance qui sépare l'individu du lieu dont il s'agit, la proximité de ce lieu aux autres et le degré d'agglomération d'un lieu par rapport aux autres dans les environs. Dans cet article nous essayons de déterminer comment ces influences fonctionnent si une frontière importante reste entre l'individu et l'espace qu'on étudie. Cette investigation utilise un modèle multivarié, calibré sur des listes de noms de villes aux Etats-Unis qu'on rappelle et qui furent générés à 9 sites canadiens différents. Nous faisons la comparaison entre ceux-ci et des résultats semblables des modèles de 22 sites aux Etats-Unis. Les résultats des tests au Canada sont plus uniformes que ceux des Etats-Unis. De plus, pour les canadiens la distance n'a aucune influence sur la probabilité de rappeler un lieu à moins que le lieu canadien ne se trouve pas très près d'une ville importante américaine située sur la frontière. Une relation forte existe entre la population d'un lieu rappelé et sa probabilité d'être rappelée. D'autres faits suggèrent également la validité d'une méthode hiérarchique de traitement des connaissances, même si ces indications sout moins fortes que ce que l'on observe aux sites américains.  相似文献   

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王磊  付建荣 《人文地理》2015,30(2):97-102
工业化和城市化之间的互动关系体现在都市区尺度上的工业区位上。本文在新经济地理学和城市地理学所揭示的产品差异化和城市集聚效应相互关系的基础上,通过区位熵分析、赫芬达尔-赫希曼指数,对美国工业区位与大都市区间的耦合关系进行实证研究。结果显示:集聚于大都市区核心区的往往是产品个性化和定制化程度较高的行业;位于大都市区外围区的大都是产品依赖于城市市场,但标准化程度较高的行业;传统制造业则往往位于非大都市区。多数都市工业的市场集中度较低,而大部分传统工业的市场集中度较高。这不仅印证了新经济地理学的理论推演和城市地理学的行业分析,而且对包括中国在内的转型国家城市及其产业发展具有重要的参考意义。  相似文献   

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