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101.
Dean M. Hanink 《Geographical analysis》1991,23(2):147-157
The characteristics of hierarchical trade flows, when placed in the context of differentiated markets, can provide some insight into the underlying bases of contemporary international trade. A model that relies on differentiated market theory and hierarchical market theory is developed. Trade characteristics derived in the model, concerning the frequency and value of trade, are empirically tested. Empirical results indicate that the model provides a useful framework for the analysis of contemporary international trade. 相似文献
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A longitudinal approach to migration behavior makes it possible to identify a sufficient condition for positive associations between rates of in-migration and rates of out-migration in the same regions. The longitudinal approach centers on the intervals of time that individuals spend in a region, and these intervals can be analyzed in terms of probability distributions or the equivalent hazard functions or survivor functions. Differences in the distributions of these intervals between subpopulations whose residence in a region begins with in-migration and subpopulations whose residence begins with other events are sufficient for temporal variations in rates of in-migration to produce variations in out-migration rates in subsequent periods of time. Tests for such differences are performed using data from the National Longitudinal Survey of Youth. 相似文献
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Hesham M. Abdel-Rahman 《Journal of regional science》1990,30(3):359-374
In this paper, I investigate some of the causes of city formation in spatial economies. A model is proposed in which an intermediate differentiated input shared by more than one industry is the cause of the formation of diversified cities. The desire of both the traded-good and the local-good industries to employ a variety of inputs from the intermediate industry provides the reason for the agglomeration of the three industries. In addition, the paper contains a comparative-statics analysis of the model in an open and a closed-city framework. It is demonstrated that the larger the city, the more variety of intermediate inputs the city can provide and the more specialized it is in the production of the traded-good. Moreover, the model suggests that different industrial structures will result in different city Sizes. 相似文献
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