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In this paper, we first develop a measure of total factor productivity (TFP) growth and summarize a source-of-growth analysis for the manufacturing sector of 48 states. As have others, we find little association between TFP growth differentials and output growth differentials for census regions. At the staterather than the regional level, however, we find a positive association between TFP growth and output growth. We use cross-sectional data to estimate the determinants of the variation in TFP growth. Two results emerge that are important for regional policy and for understanding national productivity trends. First, state investments in education and in transportation infrastructure may affect TFP growth. Second, energy price increases in the early 1970s had no differential effects on productivity growth across states. We also explore the determinants of manufacturing output growth and find that TFP growth, demand growth, wage growth, wage levels, and state corporate income tax rates are significant. 相似文献
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地理学家的演讲与他们运用文字、图象所作的交流同样值得重视.美国的地理学可以通过下述途径得到加强,即围绕地点、地区和全球联系发展实质性演讲,促进自然地理的发展,恢复地理生态的传统.地理信息系统(geographic information systems)对于完成上述任务,对于改进地理学科以满足不断出现的需要,将是一个非常有用的工具.如果我们能够避免自己拆自己的台,避免不现实的空想,避免玩弄语言技巧,而是坚持在大学里进行高质量的教学,并在教师和从事地理实践工作的人员之间开展学术交流,那么地理学将会变得更加有效.我们有一个前所未有的机会来帮助改进美国的中小学地理教育. 相似文献
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Samuel Nión-Álvarez Francisco Javier González García 《Oxford Journal of Archaeology》2023,42(1):50-70
This paper analyses social transformations in the Early Iron Age based on a holistic and longue durée approach applied to the first fortified habitats in the Iberian north-west. Through a comprehensive review of two paradigmatic settlements of the EIA in the province of A Coruña (Galicia, north-west Iberia), Punta de Muros and A Graña, a comparison is drawn between the social and territorial dynamics of this period by means of an in-depth analysis of the main characteristics of both settlements. Accordingly, a greater level of social complexity during the phases of occupation of the settlement of Punta de Muros has been identified, in contrast to the resistance to change observed in A Graña. Based on these conclusions, the role of metalworking and its symbolic value in fostering and legitimizing these social and territorial transformations and in the development of Iron Age communities are analysed. 相似文献
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Ralph E. J. Boerner Michael N. DeMers John W. Simpson Francisco J. Artigas Alejandra Silva Leslie A. Berns 《Geographical analysis》1996,28(1):56-66
This study examined landcover change during 1940–1988 in two contiguous landscapes of approximately 12,400 hectares in central Ohio, USA: an inertial till plain area and a more dynamic moraine area. Agriculture dominated both landscapes throughout, however, the cover of natural vegetation and urban-suburban development increased over time on the moraine while natural vegetation decreased and agriculture increased on the till plain. Markov process models for landcover change were constructed for three 14–17-year time intervals and for the entire forty-eight-year study period. Probabilities of self-replacement for agricultural lands (0.91–0.97) were higher and those for forests (0.54–0.65) lower than those reported for other landscapes. Predictions of landcover percentages for fifty years in the future were made using Markov process models derived from actual cover changes in 1940–1957, 1971–1988, and 1940–1988. All three models produced similar predictions for the inertial till plain area. In contrast, the three models' predictions differed considerably for the moraine area. Only the 1971–1988 transition matrix was sensitive to increases in urbanization and reforestation which began on the moraine in the 1970s. These results indicate that reliance on lengthy study intervals and net rates of change can obscure spatial and temporal patterns of landcover change that are caused by natural and socioeconomic factors operating on shorter time scales. 相似文献
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Ronald Smelser 《History of European Ideas》1983,4(4):478-479