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Policy Bubbles     
We develop the concept of a policy bubble to capture the notion of long‐term overinvestment in a policy. In sketching the relation of policy bubbles to economic bubbles, we describe how these two concepts have similar origins but different trajectories because they are filtered by different institutions. We examine in some detail three likely instances of ongoing policy bubbles: crime policy, school reform (charter schools and private education vouchers), and the contracting and privatization of public services. We show how these cases differ from the housing bubble of 1997–2007, how they differ from each other, and the extent to which they can be considered policy bubbles. Last, we suggest this concept can help unify the policy process literature with the practice of policy evaluation and outline testable hypotheses for future research.  相似文献   
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Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C3 and C4 plant-derived components, with a larger C4 component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ15N values are attributed to consumption of dietary resources from a 15N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C3 and C4 plants. The large range of δ13C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.  相似文献   
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Here we report δ13C and δ15N measurements of serial sections of human deciduous and permanent tooth dentine from archaeological samples taken from the medieval village site of Wharram Percy, Yorkshire, UK. We found a pattern of enrichment, for both δ13C and δ15N, where the tooth crown was greater than the cervical part of the root, which in turn was greater than the apical portion of the root and the associated rib collagen values. This pattern reflects a decrease in the consumption of isotopically enriched breast milk and the introduction of less enriched weaning foods in the diet. The (mean±SD) difference between the deciduous second molar crowns and corresponding rib samples from the same individuals after 2 years of age was 1.2±0.4‰ for δ13C and 3.2±0.8‰ for δ15N. The δ15N values are as predicted, but as there were no C4plants at Wharram Percy, this 1.2‰ enrichment in δ13C represents clear evidence of a carbon trophic level effect in collagen from breastfeeding infants. Carbon and nitrogen results also show that the infant diet among those who died in infancy did not differ from those who survived into childhood. This study demonstrates the promise of using dentine serial sections to study the temporal relationships of breastfeeding, weaning, and dietary patterns of single individuals.  相似文献   
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It is now three decades since Waterbolk introduced evaluation criteria to 14C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of 14C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large 14C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of 14C dates.  相似文献   
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Many indigenous populations are experiencing rural-to-urban migration. In making this transition, indigenous peoples are entering industrial societies where most income derives from wages or salaries, and formal educational achievement is crucial in determining economic prospects. This research analyzes the gap in test score results between Aboriginal and non-Aboriginal students in public schools in the Canadian province of British Columbia. It finds a strong effect of school quality, as measured by non-Aboriginal achievement, on Aboriginal achievement. It also finds a nonlinear negative relationship between Aboriginal achievement and the number of Aboriginal students in a school over the empirically observed range. It thus suggests a possible trade-off and dilemma between, on the one hand, policies that enable Aboriginal students to concentrate in a few schools able to provide a culturally sensitive curriculum and, on the other, policies to maximize Aboriginal academic achievement.  相似文献   
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This article highlights a marked growth in the number of second homes in Ireland since the mid-1990s, which is concentrated in the rural and coastal parts of the peripheral Border, Midwest, Southeast, Southwest and West regions, together with parallel growth in the number of long-term vacant dwellings in these regions. These phenomena are linked to economic and population growth, the “laissez faire” nature of land use planning in rural Ireland, the generous fiscal treatment of housing, as well as tax incentives to encourage house building in economically marginal areas. The social and economic impacts of these dwelling on individual localities vary, depending on their number, usage patterns and the nature of the local economy and housing market. However, their environmental consequences are largely negative as is their impact on the national economy and on the economies of those regions where vacant dwellings are concentrated. Thus, our research questions the value of housing-led rural development, as they can result in excessive output of vacant and second homes and highlights the importance of adequately resourcing planning authorities if the worst excesses of rural housing overdevelopment are to be avoided.  相似文献   
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