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121.
Using the newly released unregistered files of the Foreign Office Permanent Under Secretary's Department (PUSD) Macklin's documentary article examines an interesting, if somewhat arcane, ‘missing dimension’ in the history of Abyssinian Emperor Ras Tafari Makonnen, more commonly known as Haile Selassie, and his covert financial relationship with the British government following his exile to Britain in 1936 after the conquest of his country by Mussolini's Fascists, until his return in 1941. By examining how the Foreign Office employed covert politics in order to obviate disruption to its ‘official’ diplomatic strategy Macklin examines how the British government set about ‘neutralising’ the Emperor's diplomatically awkward presence in England in their pursuit of rapprochement with Mussolini through which to drive a wedge between Fascist Italy and Nazi Germany.  相似文献   
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We propose a locally efficient estimator for a class of semiparametric data combination problems. A leading estimand in this class is the average treatment effect on the treated (ATT). Data combination problems are related to, but distinct from, the class of missing data problems with data missing at random (of which the average treatment effect (ATE) estimand is a special case). Our estimator also possesses a double robustness property. Our procedure may be used to efficiently estimate, among other objects, the ATT, the two-sample instrumental variables model (TSIV), counterfactual distributions, poverty maps, and semiparametric difference-in-differences. In an empirical application, we use our procedure to characterize residual Black–White wage inequality after flexibly controlling for “premarket” differences in measured cognitive achievement. Supplementary materials for this article are available online.  相似文献   
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Five-Hundred Life-Saving Interventions and Their Cost-Effectiveness   总被引:42,自引:0,他引:42  
We gathered information on the cost-effectiveness of life-saving interventions in the United States from publicly available economic analyses. "Life-saving interventions" were defined as any behavioral and/or technological strategy that reduces the probability of premature death among a specified target population. We defined cost-effectiveness as the net resource costs of an intervention per year of life saved. To improve the comparability of cost-effectiveness ratios arrived at with diverse methods, we established fixed definitional goals and revised published estimates, when necessary and feasible, to meet these goals. The 587 interventions identified ranged from those that save more resources than they cost, to those costing more than 10 billion dollars per year of life saved. Overall, the median intervention costs $42,000 per life-year saved. The median medical intervention costs $19,000/life-year; injury reduction $48,000/life-year; and toxin control $2,800,000/life-year. Cost/life-year ratios and bibliographic references for more than 500 life-saving interventions are provided.  相似文献   
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A Simulated Annealing Approach to Communication Network Design   总被引:1,自引:0,他引:1  
This paper explores the use of the meta-heuristic search algorithm Simulated Annealing for solving a minimum cost network synthesis problem. This problem is a common one in the design of telecommunication networks. The formulation we use models a number of practical problems with hop-limit, degree and capacity constraints. Emphasis is placed on a new approach that uses a knapsack polytope to select amongst a number of pre-computed traffic routes in order to synthesise the network. The advantage of this approach is that a subset of the best routes can be used instead of the whole set, thereby making the process of designing large networks practicable. Using simulated annealing, we solve moderately large networks (up to 30 nodes) efficiently.  相似文献   
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ABSTRACT: We compare changes in the effect of child support payments on the educational attainment of children age 16 to 19 before and after passage of the Child Support Enforcement Amendments of 1984, which strengthened enforcement of child support obligations in the United States. Using 1979, 1984, and 1988 Current Population Survey data, we hypothesize and find a decline in the positive effect of child support between 1984 and 1988 that exceeds any earlier decline. Instrumental variables estimates provide additional evidence consistent with the idea that child support serves as an indicator of unobservable characteristics of noncustodial fathers who pay support.  相似文献   
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This study investigates the relationship between the carbon extractive sector in Canada and renewable energy development. Specifically, it examines the strategies employed by Canadian carbon‐capital firms to shape and control alternative energy and considers if we are witnessing signs of “transition capture” as some oil, gas, and coal firms invest in a gradual shift toward “climate capitalism.” I investigate first, investments by large Canada‐based fossil fuel companies in renewable energy and second, interlocking directorate relations between the fossil fuel sector and the renewables industry. Findings suggest the possibility of a long‐term strategic orientation toward a climate capitalist model of development by some carbon‐capital firms; however, this alignment remains highly tentative, with evidence pointing to an industry that is largely without plans for energy transition.  相似文献   
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