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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.
1850—1890年以奥斯曼为代表的统治者对巴黎城市空间进行功能性改造,塑造了巴黎新的景观社会并完成了空间生产化、秩序化、政治化的重构。资产阶级借助地租杠杆,利用空间政治工具性和政治功能性进行资本扩张的同时,也实现了阶层分化和新身份政治的形成。资本投机下的空间改造与生产使得巴黎无产阶级生存与发展的权益逐步被蚕食、侵害和剥夺,无产者对资产阶级的空间改造逐渐产生了由认同—消解—反抗的转向,空间正义意识开始觉醒。通过对城市空间规划改造中的阶级立场分析,论证空间正义与城市发展、阶层融合、社会排斥之间的联系机理,阐明资本主义空间规划与空间生产的固有缺陷,对当代城市的空间规划、贫困问题、社会排斥、城市包容性发展、环境更新与治理等现实问题提供新的视角启发与理路审视。  相似文献   
3.
"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   
4.
科技创新能够通过产业复杂度的变化对经济增长产生影响.以1995—2019年世界银行和哈佛大学Atlas数据库的科技创新为研究样本,运用中介效应检验方法,考察科技创新如何通过纺织类、农业类、钻石类、矿产类、金属类、化工类、汽车类、设备类和电子类的产业复杂度变化来影响国民生产总值,从而揭示了科技创新如何通过产业复杂度的变化影响经济增长的机理.研究结果表明:从总体上看,科技创新影响经济增长的过程中,产业复杂度的中介效应量为90.83%,具有显著性,其中农业类、钻石类以及矿产类相关系数为负,其他类别相关系数为正,电子类作用程度最高.区分经济体类型的研究结果显示:产业复杂度的中介效应存在异质性,发达经济体、亚洲经济体、技术密集型经济体存在相对优势,而且科技创新促进经济增长开启了"机会窗口期",后发经济体可以实现"弯道超车".这一研究结论有助于丰富科技创新领域的相关成果,能够为引导产业转型升级方向、提高国家经济增长能力提供理论依据和经验借鉴.  相似文献   
5.
To analyse the role of self-efficacy in goal setting in public administrations, this study combines goal-setting theory, public service motivation literature and cognitive theory. Using partial least squares structural equation modelling (PLS-SEM), survey data from 105 German civil servants are analysed. The results underline the role of goal setting (represented by goal difficulty and specificity) in determining the self-efficacy of public servants. Public service motivation and goal specificity both increase public servants’ work performance; however, the effects of goal difficulty are negatively mediated by the employee’s self-efficacy. That finding reflects the central role of self-efficacy, which should not be ignored in the goal-setting processes of public administrations.  相似文献   
6.
Longitudinal studies are the gold standard of empirical work and stress research whenever experiments are not plausible. Frequently, scales are used to assess risk factors and their consequences, and cross-lagged effects are estimated to determine possible risks. Methods to translate cross-lagged effects into risk ratios to facilitate risk assessment do not yet exist, which creates a divide between psychological and epidemiological work stress research. The aim of the present paper is to demonstrate how cross-lagged effects can be used to assess the risk ratio of different levels of psychosocial safety climate (PSC) in organisations, an important psychosocial risk for the development of depression. We used available longitudinal evidence from the Australian Workplace Barometer (N?=?1905) to estimate cross-lagged effects of PSC on depression. We applied continuous time modelling to obtain time-scalable cross effects. These were further investigated in a 4-year Monte Carlo simulation, which translated them into 4-year incident rates. Incident rates were determined by relying on clinically relevant 2-year periods of depression. We suggest a critical value of PSC?=?26 (corresponding to ?1.4 SD), which is indicative of more than 100% increased incidents of persistent depressive disorder in 4-year periods compared to average levels of PSC across 4 years.  相似文献   
7.
This article considers statistical inference for the heteroscedastic partially linear varying coefficient models. We construct an efficient estimator for the parametric component by applying the weighted profile least-squares approach, and show that it is semiparametrically efficient in the sense that the inverse of the asymptotic variance of the estimator reaches the semiparametric efficiency bound. Simulation studies are conducted to illustrate the performance of the proposed method.  相似文献   
8.
本研究运用调查分析的方法了解大城市年轻母亲在育儿过程中的感受。研究发现,夫妻共同分担家庭育儿责任的观念深入人心,母亲在孩子成长中的重要性也得到肯定。养育孩子使年轻的母亲既充满了快乐和幸福,也伴随着各种不安和焦虑;她们普遍感到育儿支援存在缺陷,以至于难以从容面对育儿过程,希望能够获得比较充裕的社会资源,有一个良好的社会支持网络,帮助她们顺利完成育儿过程。为此建议,政府应制定相应的政策法规,提供一定的资金支持,加强对处于育儿期家庭的人文关怀;进一步强化男女平等意识,促进父亲更多地参与日常育儿活动;建立网上支援系统;改善城市规划建设,为育儿提供更好的空间环境。  相似文献   
9.
Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models.  相似文献   
10.
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