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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
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The hypothesis that irritability and contingency detection are negatively correlated was examined in thirty‐one 6‐month‐old infants. Observation and maternal report‐based assessments of irritability were correlated with both a criterion score and a continuous score of contingency detection. Results indicated that greater irritability in infants was associated with lower contingency detection scores. Discussion focuses on identifying processes by which the 2 constructs may be associated. 相似文献
4.
Marc Kennedy Clive Anderson Anthony O'Hagan Mark Lomas Ian Woodward John Paul Gosling Andreas Heinemeyer 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2008,171(1):109-135
Summary. A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO2 ) concentrations in the atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 1012 g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered. 相似文献
5.
We use in-depth interviews, participant observation, and document analysis to examine women's involvement in the Gulf War Illness movement. We find that women's cumulative grievances of health concerns, financial hardships, and emotional problems opened them to movement recruitment as they surfed the Internet for information and support. The movement's division of labor was influenced not by gender but by health status. Women used the Internet to provide medical information and emotional support to geographically dispersed veterans. Activism transformed women activists by endowing them with a sense of empowerment and a somewhat broadened concern for social justice. Although their transformations disposed the women to become active on related issues, it did not extend to concerns about gender discrimination. We suggest that the next research step is to investigate gender differences in movement processes by surveying activists across a variety of movements to test propositions and to identify the characteristics of other social contexts that structurally instigate a departure from traditional gender roles. 相似文献
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Using mail survey data based on a stratified systematic sample [N = 686] of 1983–1988 graduates of a medium-sized state university, this research evaluates whether ROTC program participation constitutes an independent source of human capital in civilian labor markets by comparing postgraduate earnings (annual income), prestige and authority, and life satisfaction of ROTC program participants with those of nonparticipants. The results revealed no statistically significant ROTC program participation effects, independent of subsequent military status. ROTC program participation paid off in terms of occupational prestige and authority for those on active duty, but not for those in national guard or reserve units. Neither ROTC participation nor current military status affected income or life satisfaction levels. 相似文献
7.
Racial differences in urban neighboring 总被引:2,自引:0,他引:2
Despite mixed expectations generated by existing theories and evidence, this analysis documents clear racial differences in urban neighboring behavior. Using data from a survey of Nashville, Tennessee, residents, we show that blacks interact with their neighbors more often than whites do, and in a greater variety of ways. The only noteworthy similarity between the two groups is the positive impact of neighboring on feelings of community affect. Overall, our results support the view that neighbor relations — like other kinds of informal participation — have helped blacks cope with constrained social opportunities and provided them with access to resources unavailable through formal institutional channels.Revised version of a paper presented at the annual meeting of the American Sociological Association, San Francisco, August 1989. 相似文献
8.
The study investigates European American and Taiwanese grandmothers’ folk theories of childrearing and self‐esteem, building on an earlier comparison of mothers from the same families. Adopting methods that privilege local meanings, we bring grandmothers’ voices into the conversation about childrearing, thereby contributing to a deeper understanding of intergenerational nuances in folk theories. In each cultural case, 16 grandmothers of 3‐year‐olds participated in in‐depth interviews that were customized according to local communicative norms. Although self‐esteem emerged as a central organizing concept in the folk theories of European American mothers, grandmothers spoke in two voices, either echoing their daughters or invoking a counter‐discourse of wariness towards self‐esteem. By contrast, Taiwanese mothers and grandmothers resembled one another—but differed from their American counterparts—in treating self‐esteem as peripheral in childrearing. Results contribute to the growing consensus that self‐esteem is a culture‐specific childrearing goal and suggest that the European American tendency to valorize self‐esteem varies by generation. 相似文献
9.
Jegers Marc 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2002,13(4):432-434
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - 相似文献
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