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In this paper, we first develop a measure of total factor productivity (TFP) growth and summarize a source-of-growth analysis for the manufacturing sector of 48 states. As have others, we find little association between TFP growth differentials and output growth differentials for census regions. At the staterather than the regional level, however, we find a positive association between TFP growth and output growth. We use cross-sectional data to estimate the determinants of the variation in TFP growth. Two results emerge that are important for regional policy and for understanding national productivity trends. First, state investments in education and in transportation infrastructure may affect TFP growth. Second, energy price increases in the early 1970s had no differential effects on productivity growth across states. We also explore the determinants of manufacturing output growth and find that TFP growth, demand growth, wage growth, wage levels, and state corporate income tax rates are significant.  相似文献   
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As science becomes an increasingly crucial resource for addressing complex challenges in society, extensive demands are placed upon the researchers who produce it. Creating valuable expert knowledge that intervenes in policy or practice requires knowledge brokers to facilitate interactions at the boundary between research and policy. Yet, existing research lacks a compelling account of the ways in which brokerage is performed to gain credibility. Drawing on mixed‐method analysis of 12 policy research settings, I outline a novel set of strategies for attaining symbolic power, whereby policy experts position themselves and others via conceptual distances drawn between the “world of ideas” and the “world of policy and practice.” Disciplinary distance works to situate research as either disciplinary or undisciplinary, epistemic distance creates a boundary between complex specialist research and direct digestible outputs, temporal distance represents the separation of slow rigorous research and agile responsive analysis, and economic distance situates research as either pure and intrinsic or marketable and fundable. I develop a theoretical account that unpacks the boundaries between research communities and shows how these boundaries permit policy research actors to achieve various strategic aims.  相似文献   
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"The spread of HIV-1 in the United Kingdom is simulated by a model which integrates behavioural and epidemiological processes within a multi-regional population projection framework and represents the spatial heterogeneities in the distribution of HIV which have significant effects on transmission patterns. Analyses determine the significance of different parameters in contributing to prediction uncertainty and highlight the importance of behavioural change and international population movements."  相似文献   
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Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.  相似文献   
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An examination of the surface deposit of an Etruscan cup said to have been dug up in Cheshire suggests instead that it had been buried in Italy and brought to England in recent times. The method described here might usefully be employed to assess the provenance of buried artefacts.  相似文献   
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