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ABSTRACT. The premise of this paper is that one can discover much about the location determinants of high-technology industry by examining the location (migration) decision of workers with high-technology occupations. A model of the high-technology worker migration decision is developed that permits estimation of worker response to both personal and area characteristics, the latter chosen to mirror location factors often cited by high-technology firms as important for both the attraction and retention of their specialized work force. Logit estimates of this model between 1975 and 1980 are presented. The paper is concluded with a discussion of policy implications.  相似文献   
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"A classic case where out-migration interacted with many other geographical phenomena is provided by rural Ireland in the nineteenth century. The apparent turning point was the Great Famine of the 1840s, but the areas with the greatest suffering from starvation did not necessarily show the greatest population decline, suggesting that other forces were active. Considerable economic and social changes were already taking place before the Famine: fertility was being reduced, later marriage was becoming established and considerable emigration was already taking place. Immediately after the Famine those areas which had been hardest hit often reverted to pre-Famine conditions and did not show strong population decline until the 1870s. The Famine was a most serious event, but the modernization of Irish rural life, which linked emigration with changes in family structure, agriculture and population numbers, was more important in bringing about geographical change."  相似文献   
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The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field.  相似文献   
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We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
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