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It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting.  相似文献   
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This article extends Bourdieu’s field theory to explain how learning spaces in the Toronto folk and metal scenes create gendered access to a field-specific form of cultural capital: performance capital, or the instrumental and interpersonal skills required to perform music. Folk musicians develop performance capital in open-access spaces, such as workshops and open stages at local folk clubs, while metal musicians learn in private spaces such as garages, basements, and rented rehearsal rooms. Folk’s learning spaces are open to all aspiring musicians, while access to heavy metal’s learning spaces relies on social networks from which women are often excluded. These different processes of capital development can lead to greater or lesser opportunities for women to become cultural producers: In Toronto, women make up approximately five percent of heavy metal musicians, but almost half of practicing folk musicians.  相似文献   
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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   
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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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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   
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