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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.
The paper gives an assessment of the theoretical foundations of development planning laid in the 1950s and 1960s, and the conceptual shifts since the turbulent 1970s questioning previous patterns of macroeconomic regulation. The call today is for management styles suited to cope with evolutionary processes. Their crucial elements in the face of overall change are sensitive early diagnosis, flexible adjustment, continuous individual and social learning, the building of technological potential, and self-organization. There is an emerging search for an evolutionary ethics accepting responsibility for the further continuation of life on the planet in view of ecological constraints and recognizing basic principles of evolution such as openness, non-equilibrium, and the positive role of fluctuations in reaching higher levels of complexity and order. Value systems have an ever more explicit impact on the direction of social change.  相似文献   
3.
Summary. The cumulative number of human immunodeficiency virus (HIV) infections worldwide has reached 60 million in little over 30 years. HIV continues to spread despite a detailed understanding of the manner in which it spreads and measures which can prevent spread. Some governments have been highly successful in containing the spread of HIV through blood products and from mother to child and among injecting drug users. Lack of political will, lack of resources or challenges to widely accepted scientific evidence have held back similar interventions in other countries. It has proved much more difficult to reduce the sexual transmission of HIV in both high and low income countries. A wide range of strategies has been identified but it remains unclear which strategies deserve priority and what methods of promoting them have the greatest effect. There is ample evidence that awareness of HIV and changes in sexual behaviour have occurred widely but the penetration of information remains poor in some vulnerable groups especially adolescents and women in poorer countries. Further obstacles face those who have information about the risk. The subordinate position of women and a desire for large families are important obstacles to condom negotiation and use. Urbanization, poverty, conflict and declining public services all exacerbate unsafe sexual behaviour. We argue that so-called 'structural' interventions directed at these wider contexts of unsafe behaviour merit greater attention. Such approaches have the added benefit of being less susceptible to 'risk compensation' which has the potential to undermine strategies directed at reducing the transmission efficiency of HIV.  相似文献   
4.
Approximations of the Bayesian estimators of the survival function based on the censored data of the log-logistic distribution are obtained under squared-error and log-odds squared-error loss functions. A numerical example is presented. Through a Monte Carlo simulation study, the behavior of the approximations found by Tierney & Kadane and Lindley are compared with a method suggested by Weiss & Howlader.  相似文献   
5.
Violations of dominance in pricing judgments   总被引:1,自引:1,他引:0  
The dominance principle states that the judged price of gamble A should be equal to or greater than the judged price of gamble B whenever A's outcomes are equal to or better than the corresponding outcomes of B, holding everything else constant. Subjects often violate the dominance principle by assigning a higher price to a gamble with some probability of winning a positive amount, Y, otherwise zero, than to a superior gamble with the same chances of winning Y, otherwise winning X. Violations also occur with losses. Results are consistent with a configural-weight theory in which the decision weight for each outcome depends on the rank of the outcome with respect to the other outcomes in the lottery and the value of the outcome (zero vs. nonzero).The authors thank Shi-jie Chang, Duncan Luce, and Lisa Ordóñez for comments on an earlier draft. This research was supported by a National Science Foundation grant to the first author (BNS-8451368). Requests for reprints should be sent to Barbara Mellers, Dept. of Psychology, University of California, Berkeley, CA 94720.  相似文献   
6.
How do firm-specific, demand-related factors influence the relationship between intra-industry diversification (IID) and performance? Recent findings regarding the performance effects of IID depict a complex picture with curvilinear relationships and several contingencies. However, firm-specific contingencies on the demand side have remained unexplored. We analyze how IID relates to firm performance (market share) in the German automotive industry using panel data between 1999 and 2008. We specifically focus on a firm's high-quality brand image as a demand-side contingency. We find support for our hypotheses of complex curvilinear relationships as well as for moderating effects of brand quality. Our results have significant theoretical implications for the IID literature.  相似文献   
7.
Originally presented to the Society of Home Health Care Management of the American College of Physician Executives at its November 16, 1993, meeting in Tucson, Ariz., the program described in this article was the winner of the College's 1994 Innovations Award in Medical Quality Management, sponsored by Merck Sharp & Dohme. The program shows the potential of case management for both improvement in the quality of care and containment of costs for a managed care population with a substantial Medicaid segment. This article is part of a continuing series on innovative programs in home health care.  相似文献   
8.
Previous scholarship has demonstrated the importance of individual characteristics and structural context for understanding social capital formation. However, a developmental approach to social capital formation has, so far, been absent. In this study, I argue that social capital formation must be understood intergenerationally as well as structurally. Using hierarchical linear modeling, I investigate the hypothesized intergenerational transmission of social capital using Waves 1 and 2 of the National Longitudinal Study of Adolescent Health. The results show that, in addition to individual characteristics, neighborhood‐level factors, and school‐level variables, parental social capital is an important predictor of adolescent social capital. This study also suggests that the intergenerational transmission of social capital functions, in part, through family structure and that structural differences account for only a relatively small share of the variation in adolescent social capital. Potential explanations for these findings are discussed.  相似文献   
9.
In an effort to promote their child’s ethnic identity development, parents of transnational adoptees regularly engage in cultural exploration activities with their children. This practice is aligned with Erik Erikson’s identity theory and constructs of exploration and commitment. Using qualitative analysis of interviews with adult adoptees, this study identifies four themes common to participants including: (1) travel to one’s birth country is a transformative experience; (2) relationships with other adoptees are important; (3) adoptees feel differently about the importance of cultural activities during childhood; and (4) adoptees feel both unique in their personal ethnic identity and have feelings of marginality.  相似文献   
10.
By analyzing cinema films, specific organizational cultures can be illustrated. The culture of prison as a “total institution” is explained on the basis of the movie “The Shawshank Redemption” (1994). With regard to the developing friendship between the former banker Andy Dufresne who is innocently convicted and the homicide delinquent Ellis Boyd Redding typical characteristics of a total institution are pointed out. Furthermore, the psychological function those characteristics serve for employees, inmates and even for the society as a whole is analyzed. Central to this interpretation is thinking of the prison as a father substitute. Many interactions become comprehensible viewed in this context. Additionally, the prison represents a huge object of projection which facilitates the collective release of aggression.  相似文献   
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