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81.
Mohai P  Saha R 《Demography》2006,43(2):383-399
The number of studies examining racial and socioeconomic disparities in the geographic distribution of environmental hazards and locally unwanted land uses has grown considerably over the past decade. Most studies have found statistically significant racial and socioeconomic disparities associated with hazardous sites. However there is considerable variation in the magnitude of racial and socioeconomic disparities found; indeed, some studies have found none. Uncertainties also exist about the underlying causes of the disparities. Many of these uncertainties can be attributed to the failure of the most widely used method for assessing environmental disparities to adequately account for proximity between the hazard under investigation and nearby residential populations. In this article, we identify the reasons for and consequences of this failure and demonstrate ways of overcoming these shortcomings by using alternate, distance-based methods. Through the application of such methods, we show how assessments about the magnitude and causes of racial and socioeconomic disparities in the distribution of hazardous sites are changed. In addition to research on environmental inequality, we discuss how distance-based methods can be usefully applied to other areas of demographic research that explore the effects of neighborhood context on a range of social outcomes.  相似文献   
82.
We use genetic algorithms (GA) to solve the assembly line balancing (ALB) problem. Inparticular, we show how this technique can be used to generate feasible line balances, improve upon solutions obtained by other heuristics reported in the literature, and utilizeany one or more evaluation criteria that can be expressed in functional form. The procedure is demonstrated with two examples: (1) intimating the improvement of heuristic-generated ALB solutions by including them in the GA initial population, and (2) the possibility of balancing assembly lines with multiple criteria and side constraints. These examples suggest that GA can be a powerful tool in ALB. To investigate the utility of GA on single-criterion problems, an experiment is conducted that compares both the GA approach and conventional heuristics. Results indicate that the GA solutions are significantly improved over the heuristic solutions under the conditions studied. It is also found that the presence of heuristic-generated conventional solutions in the GA initial population leads to statistically preferred results.  相似文献   
83.
84.
In this article, we study how an expert system affects novice problem solving in a financial risk analysis domain. We demonstrate that novice performance is improved after exposure to an expert system. Further, we show that novice performance continues to improve when the system is withdrawn. By comparing learning curves for people with exposure to those without, we can assess how much the system has benefitted its users. We demonstrate a quantitative methodology to measure the increment of learning due to the use of an information technology. We also explore the issue of how expertise is transferred from the system to the user.  相似文献   
85.
86.
Lifetime Data Analysis - CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their...  相似文献   
87.
In this content analysis, researchers examine articles published from 2000 to 2015 in three family therapy journals, yielding a total of 948 empirical articles. The purpose is to provide an overview of the research being published, assess who is publishing, and investigate the current state of clinical effectiveness research in marriage and family therapy (MFT). Most first authors were affiliated with MFT programs and primarily included diversity and couples in their research. There was a significant increase of research on clinical process—though the number of clinical outcome studies held steady. There were no significant changes with regard to research funding. Implications support the use of innovative research methods to provide evidence of clinical effectiveness.  相似文献   
88.
Draus  Paul  Lovall  Sam  Formby  Treva  Baldwin  Lloyd  Lowe-Anderson  Wanda 《Urban Ecosystems》2019,22(1):91-102
Urban Ecosystems - In 2011, Marathon Petroleum Company LP, which has operated a refinery west of the Rouge River since 1959, initiated a voluntary property purchase program in the neighborhood...  相似文献   
89.
Payment by results is a relatively new way of giving development aid, where a recipient's performance against pre‐agreed measures determines the amount of aid they receive. Advocates for the mechanism argue it provides donors with both a ready justification for maintaining aid budgets and better results through innovation and autonomy. It has proved popular, with most bilateral aid donors having at least experimented with the mechanism and the variety of measures stretching from individual health workers being paid for each procedure, to national governments being paid for students' test scores. However, there has not been a robust assessment of whether Payment By Results (PbR) achieves its aims for greater effectiveness. I synthesize the evidence from eight projects fully or partially funded by DFID, the recognized world leader on PbR. This represents the best evidence currently available, and is critically analysed using the leading theoretical framework that breaks each agreement into its constituent parts. I find no evidence that PbR leads to fundamentally more innovation or autonomy, with the overall range of success and failure broadly similar to other aid projects. This may partly be due to the current use of Payment by Results, with no readily identifiable examples of projects that truly meet the idealized PbR designs. Advocates of PbR may thus conclude the idea is yet to be tested. I argue PbR does not deal with the fundamental constraints that donors face, and so it is unsurprising that PbR is subject to the normal pressures that affect all aid spending.  相似文献   
90.
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