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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.
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - To encourage methodological pluralism in the field, this paper examines an illustrative sample of articles that apply...  相似文献   
3.
功能性模型认为,提升警察信任的主要方法在于预防和控制犯罪,降低犯罪率与提升公众安全感;而表达性模型认为,提升警察信任更应注重维护社会正义与社区凝聚力。基于提出促进中国警察信任度提高的理论模型,提升公众获得感、幸福感、安全感,实现国家和社会整体安全的最终目的,采用结构方程模型验证“功能性-表达性模型”与中国警察信任关系的结果表明,功能性模型与表达性模型内部因素之间存在显著路径关系,同时功能性模型显著影响表达性模型指标进而改变公众对警察的信任程度。经调节效应分析后发现,主观社会阶层负向调节被害经历到犯罪恐惧感的直接路径,社交媒体使用负向调节犯罪恐惧感到警察信任的直接路径;在主观社会阶层和社交媒体使用的共同调节作用下,“被害经历→犯罪恐惧感→警察信任”中介路径效应值,随社交媒体使用频率的提升而增大,随主观社会阶层的升高而减小。  相似文献   
4.
Clinical Social Work Journal - System enactments are co-created phenomena characterized by confounding and emotionally charged multi-person interactions that emerge through the convergence of...  相似文献   
5.

This paper shows that mobile money technology—an electronic wallet service that allows users to deposit, transfer, and receive money using their mobile phones—is positively correlated with increased school participation of children in school age. By using data from 4 African countries, we argue that, by reducing transaction costs, and by making it easier and less expensive to receive remittances, mobile money reduces the need for coping strategies that are detrimental to child development, such as withdrawing children from school and sending them to work. We find that mobile money increases the chances of children attending school. This finding is robust to different empirical models. In a nutshell, our results show that 1 million children could start attending school in low-income countries if mobile money was available to all.

  相似文献   
6.
Environmental scanning is a broadly defined concept, having first received attention from scholars in the late 1960s. Over the years a number of similar and overlapping constructs have emerged in management literature. The aim of this study, via a systematic review and thematic analysis of relevant empirical research, is to consolidate foundation environmental scanning knowledge, demonstrate how scanning research has developed and fragmented over time, and propose an agenda for future research. The first contribution of our review is a new typology of environmental scanning research made up of five discrete research views, which provides a more comprehensive and contemporary overview of the field than previous studies. The second is a proposed agenda for future research that explicitly acknowledges the role of technology, an area that is presently underdeveloped in foundation scanning literature. The third contribution is to signpost future directions for research on scanning and organisational performance using a number of theoretical perspectives. The overall outcome of our review is to move scanning research on from increasingly incremental contributions concerned with context to a place where the changing role of technology and the mechanisms through which environmental scanning contributes to competitive advantage can be more thoroughly understood.  相似文献   
7.
Desirable system performance in the face of threats has been characterized by various management concepts. Through semistructured interviews with editors of journals in the fields of emergency response and systems management, a literature review, and professional judgment, we identified nine related and often interchangeably used system performance concepts: adaptability, agility, reliability, resilience, resistance, robustness, safety, security, and sustainability. A better understanding of these concepts will allow system planners to pursue management strategies best suited to their unique system dynamics and specific objectives of good performance. We analyze expert responses and review the linguistic definitions and mathematical framing of these concepts to understand their applications. We find a lack of consensus on their usage between interview subjects, but by using the mathematical framing to enrich the linguistic definitions, we formulate comparative visualizations and propose distinct definitions for the nine concepts. We present a conceptual framing to relate the concepts for management purposes.  相似文献   
8.
This article analyzes contests when contestants derive heterogeneous benefits from winning and investments are seen as costs to the contest designer. An example of this is sports leagues maximizing league profits. For sports leagues, optimal contests depend upon the heterogeneity of market sizes and the impact of team investment on winning. Sports leagues have mechanisms to change the structure of contests, implying they have some control of the expected payoff of teams, the value of the athletes, and the balance of the league. Data from Major League Baseball and the National Basketball Association are used to empirically estimate the model. (JEL C72, L10, L83)  相似文献   
9.
Although researchers have identified the more immediate mechanisms of change in family‐based treatments for juvenile justice‐involved youths, it is not known whether these same mechanisms continue to prevent criminal offending into adulthood. The present study evaluated whether caregiver‐directed improvements in family relations, youth prosocial peer relations, and youth academic performance during multisystemic therapy (MST) for serious and violent juvenile offenders had an impact on young adult involvement in criminal activity and sentencing 10.2 years following treatment. The results showed that improvements in family relations were associated with reduced odds of criminal outcomes a decade later for former MST participants. Furthermore, improvements in youth prosocial peer relations and academic performance were also related to lower odds of long‐term criminal activity. These results are consistent with the underlying theory of change in family‐based treatments and demonstrate that caregivers are critical to achieving and sustaining decreased antisocial behavior for youths with serious and violent criminal histories.  相似文献   
10.
This longitudinal study examined relations between mother–child relationship quality and father support in adolescence (ages 15–19) and emerging adults’ (ages 24–28) romantic anxiety and avoidance in a sample that experienced parental divorce in childhood (n = 72). A significant interactive effect of mother–adolescent relationship quality and father support on romantic anxiety occurred. High levels of father support protected emerging adults from the negative effects of a low quality mother–adolescent relationship. These results highlight the importance of examining effects of one parental relationship in the context of the other and the role that nonresidential fathers play in influencing their offspring’s romantic attachment.  相似文献   
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