Gamma-Maxwell distribution

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.     

Bayesian quantile regression for skew-normal linear mixed models

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.     

The performance of model averaged tail area confidence intervals

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.     

Parallel and interacting stochastic approximation annealing algorithms for global optimisation

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.     

Cultural Attunement in Therapy With Mexican‐Heritage Couples: A Grounded Theory Analysis of Client and Therapist Experience

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.     

The Dyadic Effects of Supportive Coparenting and Parental Stress on Relationship Quality Across the Transition to Parenthood

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.     

Predicting Follow‐up Outcomes in Emotionally Focused Couple Therapy: The Role of Change in Trust,Relationship‐Specific Attachment,and Emotional Engagement

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.     

It's About Time! Examining Received Dosage and Program Duration as Predictors of Change Among Non‐Distressed and Distressed Married Couple and Relationship Education Participants

Although Couple and Relationship Education (CRE) programs were intended to be preventive in nature, an emerging reality is that relationally distressed couples are attending programs. This has raised questions about both its general usefulness and what is known regarding predictors of change in CRE for distressed couples particularly. Previous work has identified dosage and duration as important moderators of changes, and there are myriad program contexts offered, highlighting the need to examine these among distressed couples. This study utilized a sample of community CRE participants and examined received dosage and program duration as predictors of change. Comparing results for distressed and non‐distressed participants, we found several group differences. Findings suggest that it is important to consider distress level and time spent in programs when placing participants. In addition, research should continue to examine these groups separately (or comparatively) to find out what works for whom.