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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
2.
刘晗 《成都理工大学学报(社会科学版)》2021,29(5):73-81
在美国标准化教育改革思潮和夏威夷独特教育价值观的影响下,夏威夷州开始进行大刀阔斧的标准化基础教育改革.此次改革极具鲜明特色,在规划政策推行、领导团队搭建和配套制度建设三方面的系列措施取得了阶段性成功,但同时也面临着资本过度干预教育的困境.美国夏威夷州的标准化基础教育改革为我国提供了镜鉴.我国基础教育改革需要制定统筹兼顾的教育规划,发掘本土文化的教育价值;集结教育系统的内外力量,设计分工合理的运行框架;设定并行不悖的衡量标准,放宽教育目标的达成方式;发挥宏观调控的积极作用,弥补教育管理的薄弱环节. 相似文献
3.
货币政策冲击对工业产出和价格的非对称影响,是新常态下把握好货币供给政策的方向、力度和节奏的重要参考依据,有助于提升货币供给政策的针对性、灵活性和前瞻性。局部投影方法在不同区制下,计算工业产出和价格对货币供给冲击的脉冲响应结果表明:货币供给冲击对工业产出的影响具有不确定性,且总体上表现为中性特征;而货币供给冲击对工业价格的影响不仅在不同区制下,而且在新常态前后均表现出显著的差异性和非对称性,总体来说是短期有效,长期中性的。情景设计的分析结果显示新常态下采用增加货币供给的政策来刺激工业经济是不可取的,其作用效果可能出现工业产出停滞不前,工业价格急剧飙升的工业滞胀。因此,需要从工业产业升级,工业技术创新等工业供给侧寻求工业经济新的增长点和动力机制。 相似文献
4.
5.
Has Opposition to Immigration Increased in the United States after the Economic Crisis? An Experimental Approach 下载免费PDF全文
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
6.
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
7.
韩显卿 《西南石油大学学报(社会科学版)》2019,10(4):59-66
本文在文献[1]的基础上做了进一步的试验研究,发现慢速降压过程流速对时间的依赖关系呈指数曲线形式,同时进行了慢速升压试验,同样发现流速与时间的指数关系。文中对文献[1]定义的附加残余效应系数提出了修改,重新定义为滞留分子粘弹效应系数,对降压过程和升压过程的粘弹效应系数进行了对比。通过岩心出口液浓度数据,证实了文中描述的粘弹效应机理和分子构象改变的物理模型的可靠性。 相似文献
8.
9.
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
10.
Aging in the Era of Regenerative Medicine: Analysis of Aging‐Related Representations among Canadian Researchers 下载免费PDF全文
Céline Lafontaine 《The Sociological quarterly》2015,56(1):62-79
Explicitly aimed at understanding and controlling molecular and cellular processes at the root of senescence and biological aging, regenerative medicine aspires to artificially reproduce the biological processes that enable the body to regenerate itself. This no longer involves conserving the body's state of balance by combating disease, as in clinical medicine, but rather fighting degeneration itself. From stem cell research to gene therapy to the production of replacement tissues, regenerative medicine perfectly corresponds to the logic of biomedicalization specific to postmodern society. Based on a series of 18 interviews conducted with Canadian researchers and clinicians in the field of regenerative medicine, this article seeks to understand representations of the aging body among researchers in this field. Seen from a strictly negative angle, aging is assimilated by researchers to an inevitable catastrophe that nevertheless must be combated. More closely observing the theoretical model of regenerative biology and the types of treatments developed, it can be observed, however, that this medicine of the future does not target the elderly, but rather promises youth the ability to regenerate themselves to avoid aging. 相似文献