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811.
In this paper, we introduce an extension of the generalized exponential (GE) distribution, making it more robust against possible influential observations. The new model is defined as the quotient between a GE random variable and a beta-distributed random variable with one unknown parameter. The resulting distribution is a distribution with greater kurtosis than the GE distribution. Probability properties of the distribution such as moments and asymmetry and kurtosis are studied. Likewise, statistical properties are investigated using the method of moments and the maximum likelihood approach. Two real data analyses are reported illustrating better performance of the new model over the GE model. 相似文献
812.
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
813.
Consider the standard treatment-control model with a time-to-event endpoint. We propose a novel interpretable test statistic from a quantile function point of view. The large sample consistency of our estimator is proven for fixed bandwidth values theoretically and validated empirically. A Monte Carlo simulation study also shows that given small sample sizes, utilization of a tuning parameter through the application of a smooth quantile function estimator shows an improvement in efficiency in terms of the MSE when compared to direct application of classic Kaplan–Meier survival function estimator. The procedure is finally illustrated via an application to epithelial ovarian cancer data. 相似文献
814.
The effects of under‐skilling on need for recovery,losing employment and retirement intentions among older office workers: A prospective cohort study
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Fleur G. GOMMANS Nicole W.H. JANSEN Dave STYNEN IJmert KANT Andries de GRIP 《International labour review / International Labour Office》2017,156(3-4):525-548
Based on a sample of older workers from the Maastricht Cohort Study, the authors investigate the prevalence and dynamics of self‐reported under‐skilling and its effects on workers' need for recovery, their risk of losing employment and their retirement intentions over a two‐year period. They find that being under‐skilled is associated both with higher levels of need for recovery over time and with the risk of losing employment, but not with early retirement intentions. To achieve sustainable employment, they argue, the course of under‐skilling should be monitored throughout workers' careers, enabling timely interventions to avoid its negative consequences. 相似文献
815.
Child‐Care Instability and Behavior Problems: Does Parenting Stress Mediate the Relationship?
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Child‐care instability is associated with more behavior problems in young children, but the mechanisms of this relationship are not well understood. Theoretically, this relationship is likely to emerge, at least in part, because care instability leads to increased parenting stress. Moreover, low socioeconomic status and single‐mother families may be more vulnerable to the effects of instability. This study tested these hypotheses using data from the Fragile Families and Child Wellbeing study (N = 1,675) and structural equation modeling. Three types of child‐care instability were examined: long‐term instability, multiplicity, and needing to use back‐up arrangements. Overall, findings showed little evidence that parenting stress mediated the associations between care instability and child behavior problems among the full sample. Among single‐mother and low‐income families, however, needing to use back‐up arrangements had small positive associations with parenting stress, which partially mediated the relationship between that type of care instability and child externalizing behavior problems. 相似文献
816.
Paul J. Fleming Clare Barrington Lisa D. Pearce Leonel Lerebours Yeycy Donastorg Maximo O. Brito 《Journal of sex research》2017,54(1):42-54
Ethnographic studies from numerous societies have documented the central role of male circumcision in conferring masculinity and preparing boys for adult male sexuality. Despite this link between masculinity, sexuality, and circumcision, there has been little research on these dynamics among men who have been circumcised for HIV prevention. We employed a mixed methods approach with data collected from recently circumcised men in the Dominican Republic (DR) to explore this link. We analyzed survey data collected six to 12 months post-circumcision (N = 293) as well as in-depth interviews conducted with a subsample of those men (n = 30). We found that 42% of men felt more masculine post-circumcision. In multivariate analysis, feeling more masculine was associated with greater concern about being perceived as masculine (OR = 1.70, 95% CI: 1.25–2.32), feeling more potent erections post-circumcision (OR = 2.25, 95% CI: 1.26–4.03), and reporting increased ability to satisfy their partners post-circumcision (OR = 2.30, 95% CI: 1.11–4.77). In qualitative interviews, these factors were all related to masculine norms of sexually satisfying one’s partner, and men’s experiences of circumcision were shaped by social norms of masculinity. This study highlights that circumcision is not simply a biomedical intervention and that circumcision programs need to incorporate considerations of masculine norms and male sexuality into their programming. 相似文献
817.
818.
Ryan G. Carlson Jenene Case Pease Naomi J. Wheeler Xun Liu Jessica McDonald Luke Strawn 《Marriage & Family Review》2017,53(1):48-64
Case management services for low-income couples receiving relationship education have been required by federal funding agencies. Studies examining relationship education outcomes for low-income couples have yet to address participant characteristics of those who attend case management services (e.g., distressed vs. nondistressed). Thus, this study examined the influence of baseline relationship satisfaction and demographics on attendance at case management visits for 2,628 low-income, partnered participants who attended relationship education. Findings indicated that participants who reported higher baseline relationship distress attended more family services counselor (FSC) visits. However, when we added demographics to the model, relationship distress no longer predicted FSC visits, whereas income served as a predictor for men and women, with those reporting greater monthly income attending more FSC visits. 相似文献
819.
Matthew S. Rutledge Steven A. Sass Jorge D. Ramos-Mercado 《Journal of Labor Research》2017,38(3):283-305
To assess the employment opportunities of older job-changers in the years prior to retirement, this study examines the how the breadth of occupations in which they find employment narrows as they age past their prime working years and how this differs by gender and educational attainment. The results indicate that workers who change jobs in their early 50s find employment in a reasonably similar set of occupations as prime-age workers, with opportunities narrowing at older ages. They also indicate that job opportunities broadened significantly for better-educated older workers since the late 1990s. While job opportunities now narrow significantly for less-educated men in their late 50s, this narrowing primarily occurs in the early 60s for women and better-educated men. In contrast to previous research, the study finds that employer policies that emphasize hiring from within are less important barriers to the hiring of older job-seekers. The study also finds that the narrowing of job opportunities is associated with a general decline in job quality as measured by median occupational earnings, a decline associated with differences in occupational skill requirements and the underlying economic environment. These results suggest that older hiring is not as limited to a select few occupations as it had been in previous decades, and that policy reforms aimed at increasing opportunities and improving labor market fluidity might best be served if they focused on less-educated men. 相似文献
820.
Evrim Gülbetekin Seda Bayraktar Özlenen Özkan Ömer Özkan 《Journal of Nonverbal Behavior》2017,41(4):325-343
One of the most prevalent problems in face transplant patients is an inability to generate facial expression of emotions. The purpose of this study was to measure the subjective recognition of patients’ emotional expressions by other people. We examined facial expression of six emotions in two facial transplant patients (patient A = partial, patient B = full) and one healthy control using video clips to evoke emotions. We recorded target subjects’ facial expressions with a video camera while they were watching the clips. These were then shown to a panel of 130 viewers and rated in terms of degree of emotional expressiveness on a 7-point Likert scale. The scores for emotional expressiveness were higher for the healthy control than they were for patients A and B, and these varied as a function of emotion. The most recognizable emotion was happiness. The least recognizable emotions in Patient A were fear, surprise, and anger. The expressions of Patient B scored lower than those of Patient A and the healthy control. The findings show that partial and full-face transplant patients may have difficulties in generating facial expression of emotions even if they can feel those emotions, and different parts of the face seem to play critical roles in different emotional expressions. 相似文献