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1.
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.
"通知—删除"规则的法律条文并没有赋予平台自治的空间,但是平台自治的需求已经"凸显".免责条款理论表面上能保障平台自治,但是并不符合我国的实际.归责条款理论是我国的通说,其扼杀了平台自治的空间,司法实践对此虽有调和,但是难以济事.我国的"通知—删除"规则系特定的历史背景下的产物,其在性质上仅仅是行为标准.在侵权行为的认定上,违反"通知—删除"规则的情形并非侵权的充分条件.事实上,这一行为标准的违反在侵权法上的意义仅仅作为主观过错的证据,电商平台可以反证其不具有过错.司法实践中亦有区别对待"通知—删除"规则的违反和侵权之认定的做法.明晰此点方可保障平台自治,同时亦实现电商平台对用户监管之目的.  相似文献   
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普里什文哲理散文中所具有的预言式生态思想与环保理念备受当代“生态文学”理论家的青睐。但他热衷描写狩猎场景的猎人情结却又遭到新世纪中“生态伦理”理论的诟病。其实从文本的本体性观念来理解,普里什文的诗性自然情怀、生态观念与他的猎人情结并非只有冲突的一面,他所表达出的是人对大自然万物之本能与道义之间的尺度衡量,而这种衡量也可反观当代人与自然万物之间的关系的现状,实际上表达出一种更为深刻的天人关系的批判性。  相似文献   
5.
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.
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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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   
9.
曾国藩在传统文化和家庭氛围影响下形成了浓厚的乡土情结,贯穿曾国藩一生的乡土情结为其事业和交友产生了深刻的影响。在京为官时期对同乡以及家乡的特别关注,折射出曾国藩浓浓的乡土情结。曾国藩在乡土情结的影响下创建了湘军,为其幕府的建立储备了人才,在乡土情结的感召下与同乡建立了深厚友谊,成就了一生的事业。  相似文献   
10.
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   
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