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"An empirical test of the effects of exogenous shocks upon a region's population size is conducted in the framework of an equilibrium locational model. The model emphasizes the separation of endogenous from exogenous factors, a point omitted in most empirical studies of aggregate migration. Exogenous changes are manifested in the local relative cost of living and the local relative unemployment rate. Hypotheses are tested using a national sample of youth, in addition to census, data [for the United States]. Surprisingly, a simple measure of the size of shock to a regional economy has the greatest explanatory power compared to more sophisticated measures based on prior business cycles."  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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ABSTRACT. This paper incorporates an exogenous taxing and service-providing public sector into a dynamic residential land-use model in order to examine how local-government fiscal policies alter the pace and pattern of residential development. The model is used to derive the comparative-dynamic responses to variations in the income, sales, and property taxes and public-service time paths. The results show how tax and expenditure effects systematically depend upon the anticipated relative growth rates in rents to alternative uses and vary across locations within a given urban area as well as across urban areas themselves.  相似文献   
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ABSTRACT. This paper introduces the household interactive variable input-output (HIVIO) model to measure the effect of cost variation on industrial outputs. The model produces a variety of cost elasticities that separate out impacts on industrial prices, imports, and outputs, with “own” and “cross” elasticity components. Like the conventional input-output multipliers, these cost elasticities can be useful parameters to evaluate the substituting behavior of firms and consumers. By using the 1980 Korean input-output transactions table, we find the wage and import price effects on industrial prices, outputs, and import demands.  相似文献   
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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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