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1.
This article presents a flood risk analysis model that considers the spatially heterogeneous nature of flood events. The basic concept of this approach is to generate a large sample of flood events that can be regarded as temporal extrapolation of flood events. These are combined with cumulative flood impact indicators, such as building damages, to finally derive time series of damages for risk estimation. Therefore, a multivariate modeling procedure that is able to take into account the spatial characteristics of flooding, the regionalization method top‐kriging, and three different impact indicators are combined in a model chain. Eventually, the expected annual flood impact (e.g., expected annual damages) and the flood impact associated with a low probability of occurrence are determined for a study area. The risk model has the potential to augment the understanding of flood risk in a region and thereby contribute to enhanced risk management of, for example, risk analysts and policymakers or insurance companies. The modeling framework was successfully applied in a proof‐of‐concept exercise in Vorarlberg (Austria). The results of the case study show that risk analysis has to be based on spatially heterogeneous flood events in order to estimate flood risk adequately.  相似文献   
2.
Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.  相似文献   
3.
We show that Bayesian ex post aggregation is unstable with respect to refinements. Suppose a group of Bayesians use ex post aggregation. Since it is a joint problem, each agent's problem is captured by the same model, but probabilities and utilities may vary. If they analyze the same situation in more detail, their refined analysis should preserve their preferences among acts. However, ex post aggregation could bring about a preference reversal on the group level. Ex post aggregation thus depends on how much information is used and may keep oscillating (“flipping”) as one keeps adding more information. Received: 16 April 2002/Accepted: 27 May 2002  相似文献   
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This study investigated the relative contribution of personality vs. environmental factors to the genesis of the burnout syndrome. A sample of 221 nursing students in Hamburg, Germany, were administered a battery of personality measures prior to any training. They were later asked to rate various stressors encountered during their practical training on hospital wards and also in nursing school, general aspects of ward climate, the frequency of private life events, and their own well-being on standard measures of burnout. Data were collected at seven time points over a period of 3 years, including the initial assessment (T1-T7). Only complete data sets (N = 123) were used for the analyses. Burnout scores from T2 to T7 were predicted, on the one hand, by the 36 'dispositional' scales of the initial battery and, on the other hand, by a set of 18 'experience-oriented' scales from the later questionnaire's concurrent administration. Scales reflecting well-being were predicted better by experiences than by dispositions. With scales reflecting attitudes towards oneself and patients, respectively, it was the other way around. Thus, both dispositional and experiential views of burnout receive some support here. Intraindividual change in burnout scores could not be linked to dispositional or experiential variables.  相似文献   
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We experimentally compare fast and slow decisions in a series of experiments on financial risk taking in three countries involving over 1700 subjects. To manipulate fast and slow decisions, subjects were randomly allocated to responding within 7 seconds (time pressure) or waiting for at least 7 or 20 seconds (time delay) before responding. To control for different effects of time pressure and time delay on measurement noise, we estimate separate parameters for noise and risk preferences within a random utility framework. We find that time pressure increases risk aversion for gains and risk taking for losses compared to time delay, implying that time pressure increases the reflection effect of Prospect Theory. The results for gains are weaker and less robust than the results for losses. We find no significant difference between time pressure and time delay for loss aversion (tested in only one of the experiments). Time delay also leads to less measurement noise than time pressure and unconstrained decisions, and appears to be an effective way of decreasing noise in experiments.  相似文献   
8.
Strategic management scholars have long emphasized the importance of innovation for a firm's competitive advantage and performance. However, the current state of knowledge about the strategic management of innovation is characterized by conflicting theoretical predictions, persisting knowledge gaps and theoretical inconsistencies. Adopting a ‘systematic’ approach to reviewing the literature, this paper combines different quantitative methods – co‐word analysis, cluster analysis and frequency analysis – to review 342 articles on the strategic management of innovation published in seven journals from 1992 to 2010. On the basis of these analyses, suggestions are developed for future research which could help to promote future theory development and provide relevant material for policy decisions that managers and executives have to make when they manage innovation.  相似文献   
9.
With the fall of the Berlin Wall in 1989, open migration from East to West Germany became possible. Between 1989 and 2007, roughly 10 per cent of the East’s population at the time of reunification migrated from east to west. The emigrants were predominantly young and female. This selective migration pattern led to a tremendous deficit of females in the 18–29 year old age group in eastern Germany. Overall, the sex ratio in that age group is as low as 89 females per 100 males in the east. In some rural counties, the sex ratio is 80 females per 100 males. We find that excess female emigration at the county level is associated with gender disparities in educational attainment that favour women, a labour market structure that favours men and the lower availability of potential partners with similar levels of education in eastern Germany.  相似文献   
10.
Recently, there has been an increased interest in the relationship between looking time during encoding and subsequent memory performance in imitation tasks. Hitherto, the results have been inconclusive: one line of research supporting the link between looking time and performance and another line finding no relation. The existing studies may, however, have been restricted by using small samples, limited looking time measures, and short retention intervals. We here examined the relationship between the encoding process by means of looking time as well as pupil dilation (by means of eye‐tracking technology) in sixty‐eight 20‐month‐old infants participating in an elicited imitation task and their subsequent memory performance (at an encoding test and at a 2‐week delayed recall test). Additional twenty‐two infants provided baseline measures. Simple looking time (assessed as fixation duration) did not correlate consistently with subsequent memory measures. In some cases, however, looking time correlated negatively with imitation scores. In contrast, positive correlations were found between pupil dilation and some of the memory measures, suggesting that pupil dilation may be a more sensitive tool compared to looking time measures.  相似文献   
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