A Probabilistic Framework for Risk Analysis of Widespread Flood Events: A Proof‐of‐Concept Study

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.     

Estimation of geodesic tortuosity and constrictivity in stationary random closed sets

We investigate the problem of estimating geodesic tortuosity and constrictivity as two structural characteristics of stationary random closed sets. They are of central importance for the analysis of effective transport properties in porous or composite materials. Loosely speaking, geodesic tortuosity measures the windedness of paths, whereas the notion of constrictivity captures the appearance of bottlenecks resulting from narrow passages within a given materials phase. We first provide mathematically precise definitions of these quantities and introduce appropriate estimators. Then, we show strong consistency of these estimators for unboundedly growing sampling windows. In order to apply our estimators to real data sets, the extent of edge effects needs to be controlled. This is illustrated using a model for a multiphase material that is incorporated in solid oxide fuel cells.     

Kurtosis modelling by means of the J-transformation

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.     

Flipping and ex post aggregation

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     

A longitudinal study of burnout: the relative importance of dispositions and experiences

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.     

Promoting work ability and well-being in hospital nursing: the interplay of age, job control, and successful ageing strategies

Previous research shows that work ability of nurses decreases with age. In our study we therefore addressed the following questions: Do successful ageing strategies at work in terms of selection, optimization, and compensation (SOC) support the work ability of nurses? Does SOC mediate the relationship between job control (i.e., decision opportunities at work) and work ability? Does the mediation differ between age-groups? 438 nurses (Age Range 21-63 years) completed a questionnaire in the course of an employee survey. Results show that SOC is positively related with work ability. The positive effect of job control on work ability is significantly mediated by SOC. There are stronger mediating effects for elder nurses than for younger nurses. Results indicate that the interplay of job control and SOC at work helps to maintain the work ability of nurses in nursing care.     

The role of events in ICT adoption: same-sex marriage and Twitter

ICT adoption is predominantly considered as a process conditioned by social structures, social situations of adopters, and attributes and features of technologies. What is often overlooked are the cultural forces that shape adoption experiences and processes. This paper focuses on events and event narratives as vehicles through which the efficacy of culture unfolds in technological change processes. Cultural sociology has shown how influential events can be for forming public opinions and facilitating collective action. This article considers the power of one event on a much smaller scale: the passage of same-sex marriage (SSM) law in New York in June 2011 was not only significant for marriage equality in the US but also for the operating logic of the news ecosystem in which the political decision was made ? the state house in Albany. For the journalists who covered this event on the ground, the SSM decision was the catalyst to fully embrace Twitter. Years later, the event still served as an exemplar for the potentials of Twitter and as a basis of legitimacy of associated tweeting practices reporters incorporated. This contribution is based on ethnographic research at the state house in Albany, analysis of tweets and legacy news coverage published during that period, and in-depth interviews with reporters.     

The effect of fast and slow decisions on risk taking

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.     

The Strategic Management of Innovation: A Systematic Review and Paths for Future Research

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.