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The Welfare Economics of Rural-To-Urban Migration: The Harris-Todaro Model Revisited 总被引:1,自引:0,他引:1
In this paper we extend the Harris-Todaro model of rural-to-urban migration to include urban agglomeration effects, some urban real wage flexibility, and a government budget constraint. Without employment subsidies laissez-faire migration is excessive unless real wage flexibility and agglomeration effects are high. Laissez-faire migration is too low compared with the first-best outcome supported by a subsidy, if its financing involves no costs. Simulations suggest that such a program would imply a substantial increase in taxation. If, as seems likely, an increase of this magnitude involves economic costs then the optimal outcome falls well short of first-best. 相似文献
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Jennafer Kwait Katherine Marconi Deborah Helitzer Matthew W. Rodieck Thomas Randall David Celentano 《政策研究杂志》1999,27(4):855-871
The analysis presented in this paper explores the similarities and differences between the services selected as priorities for funding by the Baltimore Ryan White CARE Act Title I Planning Council during the first 2 years of the program in this metropolitan area, and services perceived by HIV/AIDS service providers and people living with HIV/AIDS to be unmet needs. The data used for these analyses were collected as part of a study to assess the implementation and impact of the CARE Act legislation in the Baltimore eligible metropolitan area( EMS ). This project includes three interrelated components: (a) a case study of the legislatively mandated Planning Council, (b) a survey of providers representing HIV/AIDS service organizations, and (c) a qualitative field study of the perceptions of people living with HIV/AIDS about the service delivery system. Taken together, the data from these three sources describe the similarities and differences among these three groups involved in HIV/AIDS care in Baltimore, in terms of their perceptions of services needed by people living with HIV / AIDS. The conclusions drawn from this study can be used to strengthen needs assessments in Title I-EMAs throughout the United States. 相似文献
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Richard Thomas 《International Journal of Osteoarchaeology》2001,11(6):448-449
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Thomas Kleinknecht 《Berichte zur Wissenschaftsgeschichte》2005,28(2):103-113
Photography – a novel medium of scientific representation in the XIXth century array of arts and sciences. To delve into various nineteenth century academic disciplines under the heading ‘photography in the arts and sciences’ as did last year's annual conference of the History of Science Society – the interest in such a topic only partly stems from the ‘iconic turn’ that has generally enlarged the scope of the social sciences in recent years. A more poignant feature in any such present day study will probably be a basic scepticism facing the fact that in public use photographs have been manipulated in many respects. Yet, while shying away from any simple success story, a historically minded approach to changing ‘visual paradigms’ (Historische Bildwissenschaft) has begun to emerge. In this context, it has proved of considerable heuristic value to reconsider the role of early photography in an array of science, arts and technology: Since the reliance on the traditional ways of sketching reality persisted, in many an instance where photography was introduced, the thoughts the pioneer photographers had about their new, seemingly automated business, call for close attention. Thus scholarship sets up a parallel ‘discussion room’; the lively debate on the benefit of academic drawings as opposed to photographic portraits is a case in point. Some fairly specialised reports on photographically based analyses, such as electron microscopy, point to a borderline where the very idea of representation as a correspondence of reality and imagination gets blurred. Even though any ‘visual culture’ will have to shoulder the ‘burden of representation’, it is equally likely that it will offer a deeper sensibility for the intricacies entailed in the variegated ways of illustrating or mapping chosen subjects of scientific interest. Scholarship may thus somewhat control the disillusionment that by now has become the epitome of writing on photographic history. Provided with a renewed methodological awareness for the perception process and its photographic transition, historians may strike a better balance between the ever present tendencies of a realistic and an aesthetic way of picturing the world we live in. 相似文献
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