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1.
Based on intergenerational data from the Panel Study of Income Dynamics, I provide estimates of income mobility across generations for men. Special attention is paid to issues of censoring caused by a son's unemployment. Employing non‐parametric bounds estimates, I illustrate that previous income mobility estimates rely heavily on (unjustified) assumptions of exogenous selection. Assuming a son's potential income is instead a function of his reason for unemployment and work history, I re‐estimate mobility. Allowing for sampling variability, the range of feasible slopes consistent with these modified bounds restrictions is 0.27 to 0.55. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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This article focuses on the housing issues of rural migrants arising from urbanization, with particular reference to chengzhongcun, a topic with considerable impact on policymaking. An attempt is made to understand the underlying rationale of self‐help in housing and the important role of chengzhongcun in sheltering rural migrants in the context of China's rural‐urban dichotomy. As demonstrated in this study, chengzhongcun accommodate, with little in the way of government resources and assistance, millions of rural migrants because of their social accessibility and affordability. While not denying their social problems, we argue that chengzhongcun in fact act as an innovative and positive agent to promote urbanization in present day China by housing massive numbers of rural migrants and assimilating them into cities. Current government policies towards chengzhongcun have generated a wide range of interest conflicts and confrontations. The consequences of such conflicts show that the government policies were problematic and unworkable, as they violated basic market principles as well as citizen rights. Policy strategy towards the redevelopment of chengzhongcun must acknowledge their credibility in the Chinese road to urbanization and requires more thoughtful and prudent consideration of migrants' demands for affordable housing.  相似文献   
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Consumers act out roles throughout their lives. Marketers assist in this role playing by providing the wardrobes, props, and sets in the form of products and services. They also help people understand acceptable role behavior by portraying roles in their communication programs. Consumers assume new roles as they age. This article is designed to enhance understanding of the often-ignored roles that accompany aging and provides examples of and suggestions for effective marketing for these role transitions.  相似文献   
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The status quo for school science and technology is unacceptable. While the former often is required for admission to university engineering, as well as to science programmes, the latter is deemed most appropriate for less able, concrete thinkers. This situation persists, despite the fact school science tends to generate large groups of citizens who are relatively scientifically and technologically illiterate, largely as a result of its preoccupation with identifying and training potential scientists and engineers. This practice is tyrannical. It must be abandoned forthwith. A realistic alternative is a combined technology and science programme – perhaps called 'technoscience' education – that would treat science and technology as equals. Such courses may, as well, be more democratic in the sense that technological problem solving often is more natural to everyday situations that everyone may find useful, not just future scientists or engineers. A framework for combined technology and science courses is described and defended here. Originally developed through collaborative action research amongst practising teachers of science, the approach appears to be feasible, under certain – perhaps ideal – conditions. A number of changes to science and technology education may be necessary for broader implementation, not the least of which is a general retrenchment in expectations for pre-determined learning, along with adjustments to teacher education. Nevertheless, the approach is recommended because of its emphasis on: personalization, inclusion, problematization, explicitness, apprenticeship, authenticity, contextualization and freedom. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The clothing and textile industry is a major employer in many areas. It consists of a large number of small firms characterised by very poor working conditions. The need to sustain employment in the industry and improve conditions has led to several local authorities adopting a sector approach to intervention. This paper looks at the development of one particular measure, the establishment of fashion centres.  相似文献   
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Transdisciplinarity: Context, contradictions and capacity   总被引:1,自引:0,他引:1  
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Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
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