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Several studies have shown that the incidence of fractures during periods of snow and ice increases significantly and continues to persist despite preventative measures. The studies discussed in this article suggest that these predominantly consist of "walking wounded" with significant increase in demands in specific services such as the emergency department and the trauma and orthopaedic department. Traditionally, the only formal mechanism in place for most hospitals to react to extreme events is to declare a major incident. This is a binary, all or nothing response, and it is questionable whether an increase of snow and ice-related fractures would be justified in triggering such an extreme response. On the other end is the "do nothing" approach, which relies heavily on the professionalism, adaptability, and resilience of the staff to deal with the additional demand. The authors present a graded surge plan model for escalation in key resources, such as staff, space, and supplies in order to achieve the most efficient response ensuring good clinical outcome for patients.

Personality constructs, attitudes and other non-cognitive variables are often measured using rating or Likert-type scales, which does not come without problems. Especially in low-stakes assessments, respondents may produce biased responses due to response styles (RS) that reduce the validity and comparability of the measurement. Detecting and correcting RS is not always straightforward because not all respondents show RS and the ones who do may not do so to the same extent or in the same direction. The present study proposes the combination of a multidimensional IRTree model with a mixture distribution item response theory model and illustrates the application of the approach using data from the Programme for the International Assessment of Adult Competencies (PIAAC). This joint approach allows for the differentiation between different latent classes of respondents who show different RS behaviours and respondents who show RS versus respondents who give (largely) unbiased responses. We illustrate the application of the approach by examining extreme RS and show how the resulting latent classes can be further examined using external variables and process data from computer-based assessments to develop a better understanding of response behaviour and RS.

Global climate change models predict an increase in the frequency and intensity of extreme droughts, with uncertain ecological impacts across ecosystems. In particular, it is not clear when extreme droughts will elicit extreme ecological responses. For this study, we employed three complementary approaches to explore the relationships between extreme drought and ecosystem responses. First, we used global data mining to evaluate the relationship between extreme gross primary productivity and extreme precipitation from 1980 to 2013. Second, we conducted a meta‐analysis using 132 drought experiments across the globe to assess the response ratios (RRs) of above‐ground net primary productivity (ANPP) to extreme versus non‐extreme drought treatments. Third, we examined community and ecosystem responses in an alpine meadow to a drought gradient experiment, which included five precipitation treatment levels (1/12 P, 1/4 P, 1/2 P, 3/4 P, and P, where P is the growing season precipitation). This study had three key results. In our historical data mining, we found that extreme droughts elicited extreme ecological responses only 15.1% of the time. The meta‐analysis results indicated that there were no significant differences in the RRs of ANPP between the extreme versus non‐extreme drought treatments. The drought gradient experiment results revealed that although the four drought treatments were statistically extreme, only the most extreme drought treatment (1/12 P) significantly reduced ANPP over the 3 years. Meanwhile, species richness and asynchrony were significantly reduced under the 1/12 P treatment, which led to a significant reduction in productivity. Synthesis. These results suggest that extreme ecological responses to extreme drought may be less frequent than previously thought. But when they do occur, extreme ecological responses may be driven by plant community changes such as species asynchrony, species loss or species reordering. Our experimental results highlight the key role of community dynamics in determining the resistance of ecosystem productivity to extreme drought, which should be assessed when predicting ecological responses to climate change.

We investigated the effects of climato-economic harshness on extreme response style. Climato-economic theorising postulates that a more threatening climate in poorer countries, in contrast to countries with a more comforting climate and richer countries with a more challenging climate, triggers intolerance of ambiguity and uncertainty avoidance inherent to conservatism, in-group favouritism and autocracy. Scores of extreme response style at country level, a proxy of this cluster of cultural characteristics, were extracted from students' responses in the Programme for International Student Assessment to test the hypothesis. In a series of hierarchical regression analysis across 64 countries, cold demands, heat demands and GDP per capita showed a highly significant interaction effect on extreme response style, predicting in total 30.7% of the variance. Extreme response style was highest in poorer countries with higher climatic demands, and lowest in richer countries with lower climate demands. Implications are discussed.

This study investigated response styles in factual items and explored their associations with personal, contextual and cultural factors. Responses on various factual questions, cognitive tests and interviewers' observational data from a total of 152,514 respondents in 22 countries in the Programme for the International Assessment of Adult Competencies (PIAAC) were analysed. Indexes of extreme, midpoint and acquiescent response styles were extracted from Likert-scale and dichotomous responses of factual items. A general response style (GRS) with a positive loading of extreme response style and negative loadings of midpoint and acquiescent response styles was confirmed. This factor showed a similar cross-cultural patterning as another general factor from attitudinal and self-evaluative items of Likert scales in a previous study, which indicated the pervasiveness of response styles irrespective of types of survey items. In a multilevel analysis, the individual-level GRS was found to be negatively related to being male, educational level and literacy competency, and positively related to 3rd-person presence and background noise, and at country level negatively associated with socioeconomic development. Cross-level interactions were also found. Implications on the pervasiveness and nature of response styles are discussed.

Wind turbines must be designed in such a way that they can survive in extreme environmental conditions. Therefore, it is important to accurately estimate the extreme design loads. This paper deals with a recently proposed method for obtaining short-term extreme values for the dynamic responses of offshore fixed wind turbines. The 5 MW NREL wind turbine is mounted on a jacket structure (92 m high) at a water depth of 70 m at a northern offshore site in the North Sea. The hub height is 67 m above tower base or top of the jacket, i.e. 89 m above mean water level. The turbine response is numerically obtained by using the aerodynamic software HAWC2 and the hydrodynamic software USFOS. Two critical responses are discussed, the base shear force and the bending moment at the bottom of the jacket. The extreme structural responses are considered for wave-induced and wind-induced loads for a 100 year return-period harsh metocean condition with a 14.0 m significant wave height, a 16 s peak spectral period, a 50 m s − 1 (10 min average) wind speed (at the hub) and a turbulence intensity of 0.1 for a parked wind turbine. After performing the 10 min nonlinear dynamic simulations, a recently proposed extrapolation method is used for obtaining the extreme values of those responses over a period of 3 h. The sensitivity of the extremes to sample size is also studied. The extreme value statistics are estimated from the empirical mean upcrossing rates. This method together with other frequently used methods (i.e. the Weibull tail method and the global maxima method) is compared with the 3 h extreme values obtained directly from the time-domain simulations. Copyright © 2012 John Wiley & Sons, Ltd.

Summary 1. Growing recognition of the importance of climate extremes as drivers of contemporary and future ecological dynamics has led to increasing interest in studying these locally and globally important phenomena. 2. Many ecological studies examining the impacts of what are deemed climate extremes, such as heat waves and severe drought, do not provide a definition of extremity, either from a statistical context based on the long-term climatic record or from the perspective of the response of the system – are the effects extreme (unusual or profound) in comparison to normal variability? 3. A synthetic definition of an extreme climatic event (ECE) is proposed that includes ‘extremeness’ in both the driver and the response: an ECE is as an episode or occurrence in which a statistically rare or unusual climatic period alters ecosystem structure and/or function well outside the bounds of what is considered typical or normal variability. This definition is accompanied by a mechanistic framework based on the concept that extreme response thresholds associated with significant community change and altered ecosystem function must be crossed in order for an ECE to occur. 4. Synthesis. A definition and mechanistic framework for ECEs is used to identify priorities for future research that will enable ecologists to more fully assess the ecological consequences of climate extremes for ecosystem structure and function today and in a future world where their frequency and intensity are expected to increase.

The paper explores a recently developed method for statistical response load (load effect) extrapolation for application to extreme response of wind turbines during operation. The extrapolation method is based on average conditional exceedance rates and is in the present implementation restricted to cases where the Gumbel distribution is the appropriate asymptotic extreme value distribution. However, two extra parameters are introduced by which a more general and flexible class of extreme value distributions is obtained with the Gumbel distribution as a subclass. The general method is implemented within a hierarchical model where the variables that influence the loading are divided into ergodic variables and time-invariant non-ergodic variables. The presented method for statistical response load extrapolation was compared with the existing methods based on peak extrapolation for the blade out-of-plane bending moment and the tower mudline bending moment of a pitch-controlled wind turbine. In general, the results show that the method based on average conditional exceedance rates predicts the extrapolated characteristic response loads at the individual mean wind speeds well and results in more consistent estimates than the methods based on peak extrapolation. Copyright © 2011 John Wiley & Sons, Ltd.

This paper calls into question traditional methods of measuring the social desirability of items and their use in scale construction. First, we make explicit that the proper focus for desirability studies of items and traits are the rated desirabilities of the alternative item responses indicating different trait levels. Second, the results from our first study show that the relation between degree of endorsement of an item and its judged desirability level is often nonlinear and varies across items such that no general model of item desirability can be adopted that will accurately represent the relations across all items, traits, and trait levels. In addition, the nature of these relationships can vary depending on whether desirability is considered in a work or general context. Third, results from a second study indicate specifically that people when instructed to self-present in a maximally desirable manner will choose for some attributes a moderate level of endorsement (e.g., “agree”) rather than a more extreme response option (e.g., “strongly agree”). Subjects offer several different reasons for viewing the less extreme response options, which yield more moderate trait level scores, as more desirable. These reasons are linked to perceptions of the more extreme response option as being associated with negative behaviors and concerns about how others will view a more extreme response to the item. Both studies indicate that desirable responding to personality items is more complex than previously believed.

This paper analyses the effects of three pitch controller faults on the responses of an onshore wind turbine and a spar-type offshore floating wind turbine. These faults include: a stuck blade pitch actuator, a fixed value fault and a bias fault of the blade pitch sensor. The faults are modeled in the controller dynamic link library and a short-term extreme response analysis is performed using the HAWC2 simulation tool. The main objectives of this paper are to investigate how different faults affect the performance of wind turbines for condition monitoring purposes and which differences exist in the structural responses between onshore and offshore floating wind turbines. Statistical analysis of the selected response parameters are conducted using the six 1-hour stochastic samples for each load case. For condition monitoring purpose, the effects of faults on the responses at different wind speeds and fault amplitudes are investigated by comparing the same response under normal operation. The severities of the individual faults are categorized by the extreme values of structural loads and the structural components are sorted based on the magnitude of the fault effects on the extreme values. The pitch sensor fixed value fault is determined as the most severe fault case and the shaft appears as the structural component that experiences the highest risk. The effects of fault conditions on the offshore floating and the onshore wind turbines are compared to investigate the potential differences. The results show that faults cause more damage to the tower and the yaw bearing for the onshore wind turbine and more damage to the shaft for the offshore floating wind turbine. This is the pre-peer reviewed version of the following article: Etemaddar, M., Blanke, M., Gao, Z., and Moan, T. (2016) Response analysis and comparison of a spar-type floating offshore wind turbine and an onshore wind turbine under blade pitch controller faults. Wind Energ., 19: 35–50, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/we.1819/abstract . This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving

Summary Based on translation models, both Gaussian and non-Gaussian wind fields are generated using the harmony superposition method for examining the reliability of a typical wind turbine at operational and parked conditions. Using the blade aerodynamic model and multibody dynamics, wind turbine responses are calculated and then probability characteristics are analyzed in details. The short-term extreme response distribution is estimated by the average conditional exceedance rate method at each mean wind speed bin, and the long-term extreme response distribution is then determined by further integrating the short-term extreme response distribution conditional on wind speed with the distribution of mean wind speed. Additionally, crack initiation life and crack propagation life are evaluated using the linear cumulative damage theory and linear crack propagation theory, respectively. The results indicate that non-Gaussian characteristics of wind inflows have a noticeably greater influence on both extreme response and fatigue damage, and the Gaussian assumption cannot suit wind turbine in complex terrain.

Term limits are an extreme response to a perceived deficiency in the political process. In fact, turnover among legislators is much higher than generally supposed, and incumbent advantage can be reduced through campaign regulation reform. Meanwhile, citizens can continue to exercise a cherished premise of democracy — choosing their representativies and telling them when to leave.

Extreme response style (ERS) is the tendency to respond to questions on a Likert-type scale by using response options on the ends of the continuum. ERS can involve either negative or positive responses, depending on the tendency to select either very low or very high values or points. Its obverse is middle (or middling) response style (MRS). Keywords: methodology; measurement in psychology; research

— In LCD panels, motion portrayal as well as panel-addressing speed and response time are critical. They need to be balanced carefully, in particular for HDTV. It will be shown which combination of technologies, such as response-time improvement, black-frame insertion, double frame rate, and scanning backlight, can achieve CRT-like motion portrayal without demanding extreme response speeds from the panel.

Regression modeling for prediction or forecasting purposes is critically dependent on the quality of the data which are used to estimate the model parameters. Extreme response or predictor-variable values can substantially influence least-squares estimates and disproportionately affect predictions. Robust alternatives to least-squares are less sensitive to extreme observations and can provide more precise predictions. In this article diagnostic displays are used to identify extreme observations and to assess the sensitivity of least-squares parameter estimates and predictions to the inclusion of these observations in a data set. The displays are shown to aid in the interpretation of weights which robust estimators assign to influential observations.

A random vibration method is developed for the response analysis of hysteretic structural systems under stochastic two-dimensional earthquake excitations. The biaxial hysteretic restoring force is modelled by coupled non-linear differential equations; the response statistics are obtained using the equivalent linearization technique. The validity of the proposed model is appraised using available biaxial loading tests of reinforced concrete columns. A parametric study was performed to examine the significance of the effects of biaxial interaction under earthquake excitations. A practical method to evaluate the extreme response statistics is also presented.

A Personal Friends Questionnaire was administered to various groups of Egyptian subjects totalling 1028 in all. This questionnaire is composed of seventy items, each of which is to be checked either + 2, + 1, 0, −1 or −2. Extreme response scores were obtained by counting the number of times +2 or −2 were assigned by each subject. Corrected split-half reliabilities of the extreme response scores for males and females were 0.92 in both cases. The extreme response set scores are suggested as possible measures of intolerance of ambiguity. A general hypothesis was formulated according to which a social group with a higher tension level would earn a higher extreme response score than a social group with a lower tension level. The theoretical formulation of the problem in this way allowed for four predictions, about the effect on extreme response set scores of age, sex, membership of a religious minority and socio-economic status. For verification of the predictions, the social groups were matched for age, sex and religion. The four expectations were, on the whole, fulfilled.