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901.
European River Floods in a Changing World 总被引:4,自引:0,他引:4
James K. Mitchell 《Risk analysis》2003,23(3):567-574
Whereas the verdict is undecided about the effects of global warming on Europe's flood risks, it is clear that Europeans are becoming more exposed and vulnerable to floods. Losses are increasing dramatically, mainly because of population and capital moving into harm's way and also because of human-driven transformations of hydrological systems, including river basins and floodplains. 相似文献
902.
903.
Patterns of diversity in age at death are examined using e
†, a dispersion measure that equals the average expected lifetime lost at death. We apply two methods for decomposing differences
in e
†. The first method estimates the contributions of average levels of mortality and mortality age structures. The second (and
newly developed) method returns components produced by differences between age- and cause-specific mortality rates. The United
States is close to England and Wales in mean life expectancy but has higher life expectancy losses and lacks mortality compression.
The difference is determined by mortality age structures, whereas the role of mortality levels is minor. This is related to
excess mortality at ages under 65 from various causes in the United States. Regression on 17 country-series suggests that
e
† correlates with income inequality across countries but not across time. This result can be attributed to dissimilarity between
the age- and cause-of-death structures of temporal mortality reduction and intercountry mortality variation. It also suggests
that factors affecting overall mortality decrease differ from those responsible for excess lifetime losses in the United States
compared with other countries. The latter can be related to weaknesses of health system and other factors resulting in premature
death from heart diseases, amenable causes, accidents and violence. 相似文献
904.
James Benjamin Schuurmans-Stekhoven 《Social indicators research》2011,100(2):313-330
Opinion is mixed regarding the link between spiritual faith-based beliefs (SFBBs) and psychological well-being—however, most published field studies suggest a positive link. Controlled experiments demonstrate that spirituality promotes social cohesion and deters excessive self-interested behaviour. Yet past research has largely overlooked virtues (which are related to, yet distinct from, SFBB) as a rival explanation for these observations. Reviewed papers almost exclusively employed bi-variate designs incapable of answering the question “Is it God, or just missing variables?” This paper redresses this oversight by simultaneously including virtue (e.g., kindness, etc.,) and SFBB as predictors of well-being. Although simple analyses (.02 ≤ β ≤ .28) replicate the typical SFBB findings, multivariate analyses reveal that virtues (spirituality) positively (negatively) predict well-being. Since multivariate analyses (which are rarely conducted in this field) are appropriate for testing competing theories, past claims that SFBBs improve well-being appear spurious. 相似文献
905.
Information matrices are often the output produced by a decision support system. These matrices are a common method for expressing a decision situation under different decision-making scenarios. The decisions involved in designing a decision support system to generate the information matrix are important and involve several cost and benefit components. A designer needs guidance in making effective design decisions in this context. Such guidance can be provided by considering the relationships among specific design decisions, costs, and benefits. The general objective of this study is to provide a comprehensive framework for this purpose. This study is the first to develop and present a comprehensive cost-benefit framework for evaluating design decisions for a variety of scenarios. The specific objective of this research is to provide guidance regarding the number of available information dimensions to incorporate in a computer-based decision aid. Simulation experiments are conducted with a completely specified model based on the cost-benefit framework (including needed assumptions) to evaluate how many information dimensions to include for a specific information matrix size to achieve a balance between information use costs and decision quality. Based upon extensive simulation analyses for a hypothetical decision maker, the practical guideline found for designers is to include only the top half of the relevant information dimensions in any specific decision support system. Over a large number of repeating choice decisions, the savings in cognitive effort and information gathering costs clearly offset relatively minor losses in decision quality. 相似文献
906.
We consider the multiple comparison problem where multiple outcomes are each compared among several different collections of groups in a multiple group setting. In this case there are several different types of hypotheses, with each specifying equality of the distributions of a single outcome over a different collection of groups. Each type of hypothesis requires a different permutational approach. We show that under a certain multivariate condition it is possible to use closure over all hypotheses, although intersection hypotheses are tested using Boole's inequality in conjunction with permutation distributions in some cases. Shortcut tests are then found so that the resulting testing procedure is easily performed. The error rate and power of the new method is compared to existing competitors through simulation of correlated data. An example is analyzed, consisting of multiple adverse events in a clinical trial. 相似文献
907.
Recently, we developed a linear programming model to aid an electric utility company in evaluating several long-term operating decisions. Variations of this model provide insights into daily operations and valuation of supply contracts. This paper outlines the important characteristics of this class of network models including the usage of a gas storage facility, the use of market forecasts of gas prices, and the accommodation of gas contract structures. In addition, we develop a scenario optimization procedure in which demand forecasts provide scenarios. We also describe ways in which these models were automated to drive a decision support system. 相似文献
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