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The aim of this research was to adapt and validate the Concern with Acting Prejudiced (CAP) scale for a Spanish sample. This measure evaluates concern about appearing prejudiced to others or oneself and the motivation not to deviate from personal egalitarian standards. First, we completed the translation and an item content validity analysis. Then, in Study 1 (N = 198), we conducted an exploratory factor analysis. In Study 2 (N = 383), we conducted a confirmatory analysis of the unifactorial structure of the Spanish version of the scale and examined its validity. In Study 3 (N = 89), we explored the moderating role of participants’ concern with acting prejudiced in the relation between implicit prejudice and explicit prejudice. The results confirmed the unifactorial structure of the scale, its appropriate psychometric properties and its predictive validity. Moreover, we confirmed that the CAP moderated the relation between implicit and explicit prejudice. In participants with a low concern with acting prejudiced, implicit prejudice was positively related with modern prejudice; in participants with a high concern with acting prejudiced, these variables were not related.  相似文献   
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The skew-generalized-normal distribution [Arellano-Valle, RB, Gómez, HW, Quintana, FA. A new class of skew-normal distributions. Comm Statist Theory Methods 2004;33(7):1465–1480] is a class of asymmetric normal distributions, which contains the normal and skew-normal distributions as special cases. The main virtues of this distribution is that it is easy to simulate from and it also supplies a genuine expectation–maximization (EM) algorithm for maximum likelihood estimation. In this paper, we extend the EM algorithm for linear regression models assuming skew-generalized-normal random errors and we develop a diagnostics analyses via local influence and generalized leverage, following Zhu and Lee's approach. This is because Cook's well-known approach would be more complicated to use to obtain measures of local influence. Finally, results obtained for a real data set are reported, illustrating the usefulness of the proposed method.  相似文献   
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The experience and competence of CEOs may have a positive influence on the performance of firms. Using secondary data on the performance of 73 Brazilian listed companies and primary data collected through a survey of the social and demographic characteristics of CEOs we tested a set of hypotheses concerning the influence of CEOs on the performance of the firms they headed between 1997 and 2012. Specifically, we examined the relationships between CEOs’ experience and competence regarding common accounting indicators. The results indicate that CEOs with diverse experience would not do better in dynamic environments, and that specific experience has a negative effect on performance. Furthermore, CEOs with formal education do not show better short‐term performance, and tenure has an inverted U‐shaped relationship with the firm's performance. This article helps to provide a better understanding of the behavior of Brazilian CEOs by examining their characteristics.  相似文献   
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In this paper, we present a multivariate version of the skewed log-Birnbaum–Saunders regression model. This new family of distributions holds good properties such as marginal variables following univariate skewed log-Birnbaum–Saunders distributions, besides presenting the usual log-Birnbaum–Saunders distribution as a particular case. Furthermore, the model parameters are estimated through maximum-likelihood methods, a closed-form expression for the Fisher’s information matrix is presented, and testing hypothesis for model parameters is performed. Two real datasets are analyzed and results are discussed.  相似文献   
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(alpha )-Stable distributions are a family of probability distributions found to be suitable to model many complex processes and phenomena in several research fields, such as medicine, physics, finance and networking, among others. However, the lack of closed expressions makes their evaluation analytically intractable, and alternative approaches are computationally expensive. Existing numerical programs are not fast enough for certain applications and do not make use of the parallel power of general purpose graphic processing units. In this paper, we develop novel parallel algorithms for the probability density function and cumulative distribution function—including a parallel Gauss–Kronrod quadrature—, quantile function, random number generator and maximum likelihood estimation of (alpha )-stable distributions using OpenCL, achieving significant speedups and precision in all cases. Thanks to the use of OpenCL, we also evaluate the results of our library with different GPU architectures.  相似文献   
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Partially linear models (PLMs) are an important tool in modelling economic and biometric data and are considered as a flexible generalization of the linear model by including a nonparametric component of some covariate into the linear predictor. Usually, the error component is assumed to follow a normal distribution. However, the theory and application (through simulation or experimentation) often generate a great amount of data sets that are skewed. The objective of this paper is to extend the PLMs allowing the errors to follow a skew-normal distribution [A. Azzalini, A class of distributions which includes the normal ones, Scand. J. Statist. 12 (1985), pp. 171–178], increasing the flexibility of the model. In particular, we develop the expectation-maximization (EM) algorithm for linear regression models and diagnostic analysis via local influence as well as generalized leverage, following [H. Zhu and S. Lee, Local influence for incomplete-data models, J. R. Stat. Soc. Ser. B 63 (2001), pp. 111–126]. A simulation study is also conducted to evaluate the efficiency of the EM algorithm. Finally, a suitable transformation is applied in a data set on ragweed pollen concentration in order to fit PLMs under asymmetric distributions. An illustrative comparison is performed between normal and skew-normal errors.  相似文献   
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Journal of Nonverbal Behavior - Facial expressions contribute to nonverbal communication, social coordination, and interaction. Facial expressions may reflect the emotional state of the expressor,...  相似文献   
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Transfusion-transmitted malaria (TTM) is a public health problem in endemic and nonendemic areas. The Brazilian Ministry of Health (MH) requested the development of a nucleic acid amplification test (NAT) for the detection of Plasmodium spp. in public blood centers to increase blood safety.  相似文献   
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This article examines the effect of tobacco prices on the decision to start smoking in Argentina. Argentina is an interesting case to explore given its high smoking rates, its recent experience with periods of very high and hyperinflation, and the mixed evidence of the effect of prices on smoking onset, particularly in low‐ and middle‐income countries. We used data from four cycles of two large national surveys conducted between 2005 and 2011 and discrete‐time hazard models. We found that tobacco prices had a statistically significant and fairly large impact on the hazard of smoking onset, and these findings were robust to alternative specifications. We also found that prices had little effect on the hazards of smoking onset during periods of hyper‐ and very high inflation, which provide some support for the notion that prices lose their informational role in such periods. Governments need to be cognizant that their most important policy tool to reduce tobacco use—taxes that increase real tobacco prices—is likely no longer effective during these times. (JEL C41, H20, I12, I18)  相似文献   
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