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1.
Dennis Wagenaar Tiaravanni Hermawan Marc J. C. van den Homberg Jeroen C. J. H. Aerts Heidi Kreibich Hans de Moel Laurens M. Bouwer 《Risk analysis》2021,41(1):37-55
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer. 相似文献
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Has Opposition to Immigration Increased in the United States after the Economic Crisis? An Experimental Approach
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Mathew J. Creighton Amaney Jamal Natalia C. Malancu 《The International migration review》2015,49(3):727-756
We employ two population‐level experiments to accurately measure opposition to immigration before and after the economic crisis of 2008. Our design explicitly addresses social desirability bias, which is the tendency to give responses that are seen favorably by others and can lead to substantial underreporting of opposition to immigration. We find that overt opposition to immigration, expressed as support for a closed border, increases slightly after the crisis. However, once we account for social desirability bias, no significant increase remains. We conclude that the observed increase in anti‐immigration sentiment in the post‐crisis United States is attributable to greater expression of opposition rather than any underlying change in attitudes. 相似文献
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雷锋的生命价值从历史、空间、境界三重维度上表现为延伸性、普遍性和超越性。雷锋的生命价值符合人与社会全面发展进步的需要,即符合人的超越性的要求、符合群体共同发展的要求、符合中华民族道德实践的要求、符合中国共产党的宗旨要求,是对生命为什么有价值、生命价值是什么、怎样实现生命价值问题的直接解答。 相似文献
5.
Cancho Vicente G. Macera Márcia A. C. Suzuki Adriano K. Louzada Francisco Zavaleta Katherine E. C. 《Lifetime data analysis》2020,26(2):221-244
Lifetime Data Analysis - Frailty models are generally used to model heterogeneity between the individuals. The distribution of the frailty variable is often assumed to be continuous. However, there... 相似文献
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A conformance proportion is an important and useful index to assess industrial quality improvement. Statistical confidence limits for a conformance proportion are usually required not only to perform statistical significance tests, but also to provide useful information for determining practical significance. In this article, we propose approaches for constructing statistical confidence limits for a conformance proportion of multiple quality characteristics. Under the assumption that the variables of interest are distributed with a multivariate normal distribution, we develop an approach based on the concept of a fiducial generalized pivotal quantity (FGPQ). Without any distribution assumption on the variables, we apply some confidence interval construction methods for the conformance proportion by treating it as the probability of a success in a binomial distribution. The performance of the proposed methods is evaluated through detailed simulation studies. The results reveal that the simulated coverage probability (cp) for the FGPQ-based method is generally larger than the claimed value. On the other hand, one of the binomial distribution-based methods, that is, the standard method suggested in classical textbooks, appears to have smaller simulated cps than the nominal level. Two alternatives to the standard method are found to maintain their simulated cps sufficiently close to the claimed level, and hence their performances are judged to be satisfactory. In addition, three examples are given to illustrate the application of the proposed methods. 相似文献
7.
建立健全领导干部党性修养评价机制,是加强党的执政能力建设,建设高素质执政骨干队伍的客观需要。坚定的政治信念、牢固的党纪意识、严谨的自律能力、优秀的道德品质和勤勉的工作作风是评价领导干部党性修养的主要内容。要明确评价领导干部党性修养的指导思想、评价主体和评价原则,要建立健全领导干部党性修养的评价指标体系,不断探索科学的评价领导干部党性修养的方式方法。 相似文献
8.
王程辉 《湖南科技大学学报(社会科学版)》2015,18(5):145-151
路易斯·卡罗尔著名小说《爱丽丝仙境漫游》至少包含4首模仿经典诗歌的戏仿诗歌。戏仿诗歌展现了其内嵌或隐身于其他文本的特点。这一特点与戏仿反对说教的娱乐性结合,共同行使了戏仿潜在的挽救性功能,使人们永远铭记可能落入湮没无闻状态的诗人及作品。戏仿作品以喜闻乐见的方式,与严肃文学相互作用,不失为读者熟悉、研读严肃文学的一个捷径。 相似文献
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Robert C. Cope Joshua V. Ross Talia A. Wittmann Michael J. Watts Phillip Cassey 《Risk analysis》2019,39(1):35-53
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments. 相似文献