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This study examines a key component of environmental risk communication; trust and credibility. The study was conducted in two parts. In the first part, six hypotheses regarding the perceptions and determinants of trust and credibility were tested against survey data. The hypotheses were supported by the data. The most important hypothesis was that perceptions of trust and credibility are dependent on three factors: perceptions of knowledge and expertise; perceptions of openness and honesty; and perceptions of concern and care. In the second part, models were constructed with perceptions of trust and credibility as the dependent variable. The goal was to examine the data for findings with direct policy implications. One such finding was that defying a negative stereotype is key to improving perceptions of trust and credibility.  相似文献   
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We propose a multiple imputation method to deal with incomplete categorical data. This method imputes the missing entries using the principal component method dedicated to categorical data: multiple correspondence analysis (MCA). The uncertainty concerning the parameters of the imputation model is reflected using a non-parametric bootstrap. Multiple imputation using MCA (MIMCA) requires estimating a small number of parameters due to the dimensionality reduction property of MCA. It allows the user to impute a large range of data sets. In particular, a high number of categories per variable, a high number of variables or a small number of individuals are not an issue for MIMCA. Through a simulation study based on real data sets, the method is assessed and compared to the reference methods (multiple imputation using the loglinear model, multiple imputation by logistic regressions) as well to the latest works on the topic (multiple imputation by random forests or by the Dirichlet process mixture of products of multinomial distributions model). The proposed method provides a good point estimate of the parameters of the analysis model considered, such as the coefficients of a main effects logistic regression model, and a reliable estimate of the variability of the estimators. In addition, MIMCA has the great advantage that it is substantially less time consuming on data sets of high dimensions than the other multiple imputation methods.  相似文献   
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Seasonal fractional ARIMA (ARFISMA) model with infinite variance innovations is used in the analysis of seasonal long-memory time series with large fluctuations (heavy-tailed distributions). Two methods, which are the empirical characteristic function (ECF) procedure developed by Knight and Yu [The empirical characteristic function in time series estimation. Econometric Theory. 2002;18:691–721] and the Two-Step method (TSM) are proposed to estimate the parameters of stable ARFISMA model. The ECF method estimates simultaneously all the parameters, while the TSM considers in the first step the Markov Chains Monte Carlo–Whittle approach introduced by Ndongo et al. [Estimation of long-memory parameters for seasonal fractional ARIMA with stable innovations. Stat Methodol. 2010;7:141–151], combined with the maximum likelihood estimation method developed by Alvarez and Olivares [Méthodes d'estimation pour des lois stables avec des applications en finance. Journal de la Société Française de Statistique. 2005;1(4):23–54] in the second step. Monte Carlo simulations are also used to evaluate the finite sample performance of these estimation techniques.  相似文献   
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This exploratory study aimed to examine which components of early childhood conscience predicted bullying involvement around school entry. In the population‐based Generation R Study, teacher reports of bullying involvement and parent reports of conscience were available for 3,244 children (M age = 6.7 years). Higher levels of overall conscience predicted lower bullying perpetration scores, independently of intelligence quotient, temperamental traits and sociodemographic characteristics. Particularly, the subscales guilt, confession, and internalized conduct, and to a lesser extent empathy, predicted bullying perpetration. Conscience was not related to victimization. Similar results were found using observations during so‐called ‘cheating games’ (subsample N = 450 children). Findings suggest that improving children's understanding of moral standards and norms may be a potential target for bullying intervention programs in early primary school.  相似文献   
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In this article, we develop the theory of k-factor Gegenbauer Autoregressive Moving Average (GARMA) process with infinite variance innovations which is a generalization of the stable seasonal fractional Autoregressive Integrated Moving Average (ARIMA) model introduced by Diongue et al. (2008 Diongue, A.K., Guégan, D. (2008). Estimation of k-Factor GIGARCH Process: A Monte Carlo Study. Communications in Statistics-Simulation and Computation 37:20372049.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). Stationarity and invertibility conditions of this new model are derived. Conditional Sum of Squares (CSS) and Markov Chains Monte Carlo (MCMC) Whittle methods are investigated for parameter estimation. Monte Carlo simulations are also used to evaluate the finite sample performance of these estimation techniques. Finally, the usefulness of the model is corroborated with the application to streamflow data for Senegal River at Bakel.  相似文献   
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At-work exercises are commonly recommended for computer operators. This randomized control trial assessed adherence, pain and satisfaction after 4 weeks of at-work exercise. Subjects (n=72) were randomized into 3 groups: resistance exercise, stretching, and control. Outcomes included a satisfaction survey, a visual analogue pain scale (VAS), a pain drawing, and the Neck Disability Index (NDI). The VAS, the drawing, and NDI were analyzed together as a composite variate referred to as Pain Impact. Exercise frequency was similar across the 3 groups (median=1.5 times per day). No differences were found between groups on Pain Impact p=0.714) or individual pain variables. Most satisfaction survey item scores did not differ between groups. However, a significant difference between groups on the survey item related to discomfort. The resistance and stretching group differed from the control group with regard to their perception that the exercises were helpful in reducing discomfort in the back and neck (p<0.001). We conclude that most subjects found the resistance and the stretching exercises easy to do, performed them 1 to 2 times daily, and said they reduced discomfort. To determine optimal type and frequency of at-work exercises, further study is needed.  相似文献   
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Review of Economics of the Household - Previous studies have shown that childrearing has a different impact on a mother’s professional career, depending, among other reasons, on how much time...  相似文献   
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Lotteries are one of the most prevalent forms of gambling and generate substantial state revenues. They are also argued to be one of the least harmful forms of gambling. This paper is one of the first to examine exclusive lottery gamblers and compares their gambling patterns and problems as well other associated risky behaviours to those who are not exclusive lottery gamblers. Data were derived from two large surveys conducted with representative adult samples in France (n?=?15,635) and Québec (n?=?23,896). Participants were separated into two groups: exclusive lottery gamblers (ELGs) and non-exclusive lottery gamblers. Using multivariate analysis, study results reveal that ELGs, who represent two thirds of gamblers, generally exhibit less intensive gambling patterns and are less likely to report other risky behaviours. However, harms associated with moderate risk and problem gambling are found to be concentrated in specific subpopulations for both groups, primarily males, older individuals, and those who report lower income and education level. Given widespread participation in lotteries and concentration of harm within specific subgroups, these findings point to the need for prevention efforts despite the lower levels of harm associated with lottery gambling.  相似文献   
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