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971.
We introduce a new family of distributions suitable for fitting positive data sets with high kurtosis which is called the Slashed Generalized Rayleigh Distribution. This distribution arises as the quotient of two independent random variables, one being a generalized Rayleigh distribution in the numerator and the other a power of the uniform distribution in the denominator. We present properties and carry out estimation of the model parameters by moment and maximum likelihood (ML) methods. Finally, we conduct a small simulation study to evaluate the performance of ML estimators and analyze real data sets to illustrate the usefulness of the new model.  相似文献   
972.
A new two-parameter distribution, the gamma-Maxwell distribution, isproposed and studied. We generate the new distribution using the gamma-G generator of distributions. The proposal distribution can be seen as an extension of the Maxwell distribution with more flexibility in terms of the distribution asymmetry and kurtosis. We study some probability properties, discuss maximum-likelihood estimation and present a real data application indicating that the new distribution can improve the ordinary Maxwell distribution in fitting real data.  相似文献   
973.
Linear mixed models have been widely used to analyze repeated measures data which arise in many studies. In most applications, it is assumed that both the random effects and the within-subjects errors are normally distributed. This can be extremely restrictive, obscuring important features of within-and among-subject variations. Here, quantile regression in the Bayesian framework for the linear mixed models is described to carry out the robust inferences. We also relax the normality assumption for the random effects by using a multivariate skew-normal distribution, which includes the normal ones as a special case and provides robust estimation in the linear mixed models. For posterior inference, we propose a Gibbs sampling algorithm based on a mixture representation of the asymmetric Laplace distribution and multivariate skew-normal distribution. The procedures are demonstrated by both simulated and real data examples.  相似文献   
974.
We investigate the exact coverage and expected length properties of the model averaged tail area (MATA) confidence interval proposed by Turek and Fletcher, CSDA, 2012, in the context of two nested, normal linear regression models. The simpler model is obtained by applying a single linear constraint on the regression parameter vector of the full model. For given length of response vector and nominal coverage of the MATA confidence interval, we consider all possible models of this type and all possible true parameter values, together with a wide class of design matrices and parameters of interest. Our results show that, while not ideal, MATA confidence intervals perform surprisingly well in our regression scenario, provided that we use the minimum weight within the class of weights that we consider on the simpler model.  相似文献   
975.
976.
We present the parallel and interacting stochastic approximation annealing (PISAA) algorithm, a stochastic simulation procedure for global optimisation, that extends and improves the stochastic approximation annealing (SAA) by using population Monte Carlo ideas. The efficiency of standard SAA algorithm crucially depends on its self-adjusting mechanism which presents stability issues in high dimensional or rugged optimisation problems. The proposed algorithm involves simulating a population of SAA chains that interact each other in a manner that significantly improves the stability of the self-adjusting mechanism and the search for the global optimum in the sampling space, as well as it inherits SAA desired convergence properties when a square-root cooling schedule is used. It can be implemented in parallel computing environments in order to mitigate the computational overhead. As a result, PISAA can address complex optimisation problems that it would be difficult for SAA to satisfactory address. We demonstrate the good performance of the proposed algorithm on challenging applications including Bayesian network learning and protein folding. Our numerical comparisons suggest that PISAA outperforms the simulated annealing, stochastic approximation annealing, and annealing evolutionary stochastic approximation Monte Carlo.  相似文献   
977.
978.
There is a need for culturally attuned approaches for couple therapy with Mexican/Mexican‐Americans. This qualitative grounded theory study utilized interviews with 11 client couples of Mexican heritage and 14 marital and family therapists to shed light on how Latino and non‐Latino therapists co‐construct positive experiences of cultural attunement with Mexican and Mexican‐American couple clients. Analysis identified a model of cultural connection through personal engagement with four interrelated phases: (a) mutual invitation, (b) shared engagement, (c) expanding personal connection, and (d) creating cultural connections. Clients in this study valued professionalism and expertise of the therapist, but felt attuned to and respected when therapists demonstrated humility, shared personal stories and emotion, and engaged in a collaborative process.  相似文献   
979.
The transition to first‐time parenthood can be challenging for couples. Using a sample of 848 ethnically diverse couples from the Fragile Families and Child Wellbeing Study across the first 3 years of parenthood, we investigated the longitudinal and dyadic associations of each parents’ parental stress, supportive coparenting, and relationship quality. Results from an actor–partner interdependence model indicated that supportive coparenting significantly predicted higher relationship quality for both mothers and fathers. Fathers’ supportive coparenting significantly buffered the effects of mothers’ parental stress on relationship quality. Also, the unique dyadic contexts of each parents’ supportive coparenting, and also both partners’ parental stress were significantly associated with relationship quality. Clinical implications from these findings are discussed through commonly used clinical theories.  相似文献   
980.
Emotionally Focused Couple Therapy (EFT), an evidence‐based couple therapy (Johnson, Hunsley, Greenberg, & Schindler, 1999), strives to foster lasting change through the creation of secure attachment bonds in distressed couples. Although studies have demonstrated lasting change in follow‐up (Wiebe et al., in press), research is needed to investigate predictors of long‐term outcomes. Our goal was to investigate predictors of long‐term outcomes in relationship satisfaction. Relationship satisfaction was assessed across 24 months in a sample of 32 couples who received an average of 21 EFT sessions. Decreases in attachment avoidance were most predictive of higher relationship satisfaction across follow‐up. These findings support the theoretical assumption that EFT helps couples foster lasting change in relationship satisfaction through the facilitation of secure attachment bonds.  相似文献   
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