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71.
Rising healthcare costs have sparked debate about the best way to provide high‐quality affordable health insurance. We discuss the potential for regulated insurance markets to outperform single‐payer public insurance. We use as an example the private Medicare plans that now provide insurance to almost a third of seniors in the United States. The evidence suggests that private plans can limit costs and potentially appeal to enrollees, and that well‐designed risk adjustment can mitigate market failures due to adverse selection. However, fostering competition between insurers, especially in smaller markets, is difficult. We discuss how future research might illuminate the relative advantages of public and private health insurance.  相似文献   
72.
In geostatistics and also in other applications in science and engineering, it is now common to perform updates on Gaussian process models with many thousands or even millions of components. These large‐scale inferences involve modelling, representational and computational challenges. We describe a visualization tool for large‐scale Gaussian updates, the ‘medal plot’. The medal plot shows the updated uncertainty at each observation location and also summarizes the sharing of information across observations, as a proxy for the sharing of information across the state vector (or latent process). As such, it reflects characteristics of both the observations and the statistical model. We illustrate with an application to assess mass trends in the Antarctic Ice Sheet, for which there are strong constraints from the observations and the physics.  相似文献   
73.
Most existing reduced-form macroeconomic multivariate time series models employ elliptical disturbances, so that the forecast densities produced are symmetric. In this article, we use a copula model with asymmetric margins to produce forecast densities with the scope for severe departures from symmetry. Empirical and skew t distributions are employed for the margins, and a high-dimensional Gaussian copula is used to jointly capture cross-sectional and (multivariate) serial dependence. The copula parameter matrix is given by the correlation matrix of a latent stationary and Markov vector autoregression (VAR). We show that the likelihood can be evaluated efficiently using the unique partial correlations, and estimate the copula using Bayesian methods. We examine the forecasting performance of the model for four U.S. macroeconomic variables between 1975:Q1 and 2011:Q2 using quarterly real-time data. We find that the point and density forecasts from the copula model are competitive with those from a Bayesian VAR. During the recent recession the forecast densities exhibit substantial asymmetry, avoiding some of the pitfalls of the symmetric forecast densities from the Bayesian VAR. We show that the asymmetries in the predictive distributions of GDP growth and inflation are similar to those found in the probabilistic forecasts from the Survey of Professional Forecasters. Last, we find that unlike the linear VAR model, our fitted Gaussian copula models exhibit nonlinear dependencies between some macroeconomic variables. This article has online supplementary material.  相似文献   
74.
We investigate the impacts of complex sampling on point and standard error estimates in latent growth curve modelling of survey data. Methodological issues are illustrated with empirical evidence from the analysis of longitudinal data on life satisfaction trajectories using data from the British Household Panel Survey, a national representative survey in Great Britain. A multi-process second-order latent growth curve model with conditional linear growth is used to study variation in the two perceived life satisfaction latent factors considered. The benefits of accounting for the complex survey design are considered, including obtaining unbiased both point and standard error estimates, and therefore correctly specified confidence intervals and statistical tests. We conclude that, even for the rather elaborated longitudinal data models that were considered, estimation procedures are affected by variance-inflating impacts of complex sampling.  相似文献   
75.
This paper explores adolescents' definitions of what it means to be a man and a woman, the psycho-social context surrounding the formation of gender ideologies and their relationship to HIV/STI prevention. Semi-structured, in-depth interviews were conducted with fifty African-American adolescents living in Baltimore, Maryland. Female gender ideologies included economic independence, emotional strength and caretaking. Male gender ideologies emphasized financial responsibility, toughness and sexual prowess. Findings suggest that stronger adherence to male gender ideologies related to toughness and sexual prowess is influenced by male participants' perceived inability to fulfill their primary gender role as economic providers and the importance of gaining approval from male peers in the absence of adult male role models. Stronger adherence to female gender ideologies related to emotional strength and caretaking may be linked to a heightened desire for male intimacy and tolerance of male sexual risk behavior. Implications of the gender ideologies documented and their commonalities are discussed in terms of HIV/STI prevention.  相似文献   
76.
Among working aged adults (18-64) with disabilities, three out of 10 (32%) work full or part-time, compared to eight out of 10 (81%) of those without disabilities [9]. In addition, 24.7% of women with a severe disability and 27.8% of men with a severe disability are employed, while women with a non-severe disability have an employment rate of 68.4% and men with a non-severe disability have an employment rate of 85.1% [14]. This study examined data from the Behavioral Risk Factor Surveillance Survey from 1995-2002 to determine whether or not disparities exist in the rate of unemployment for women with disabilities, compared to men with disabilities and women and men without disabilities. In addition, regression analysis looked at the how disability and gender predict the outcome of unemployment. Results showed that there has been essentially no change with regard to employment for any of these populations. In addition, disability and gender were found to be the strongest predictors of unemployment for women with disabilities. Possible explanations were discussed as to the reasons for the results and issues were presented for future research.  相似文献   
77.
Despite the numerous benefits of physical activity, older adults continue to be more sedentary than their younger counterparts, and sedentary behavior is more prevalent among older racial and ethnic minorities than among Whites. This study used the nominal group technique (NGT) to examine participants' perceptions of what neighborhood environmental changes would encourage greater physical activity for older African American and Hispanic women. Participants age 50-75 years were recruited from 2 urban community health clinics. Nine NGT sessions (45 participants) were conducted. The women were asked what changes in their neighborhood environment would encourage them to become more physically active. Responses to the research question were tabulated, and qualitative analysis was used to identify themes and categories. Major categories were physical environment changes, safety, and activities/social support. Although the physical environment received the greatest number of points, concerns for personal safety cut across categories. Participants indicated the need for more facilities in which to be active.  相似文献   
78.
This study investigates the impact of personal finance education delivered in high school and college. Outcomes of interest were investment knowledge and household savings rates measured years after the financial education was delivered. A web-based survey with questions about participation in financial education, financial experiences, income and inheritances, and demographic characteristics was administered to 1,039 alumni from a large midwestern university. Participation in a college level personal finance course was associated with higher levels of investment knowledge. Experience with financial instruments appeared to explain more of the variance in both investment knowledge and savings rates. No significant relationship between taking a high school course and investment knowledge was found. Financial experiences were found to be positively associated with savings rates.
Garrett CravenerEmail:
  相似文献   
79.
Women's fear of violence can impact negatively on their active participation in life. An ageing survey conducted with 2,620 Australian respondents aged 50 to 90 years examined aspects of work, learning, social, spiritual and emotional status, health, vision, home, life events, demographics, and asked an open-ended question about what being actively engaged in life meant. Ordinal regression was carried out on two dependent variables: wanting and needing to learn to discourage violence. Analyses found that as women's age increased, those on lower incomes were more likely than others to say they needed to learn how to discourage violence against them. This paper investigates the variables associated with the findings-transport, finances, news media, home safety, and reduced social interactions. Results highlight the importance of understanding women's fear in the context of personal and social issues, and the need to provide learning opportunities to improve safety and social engagement.  相似文献   
80.
Earth-spirited faiths (e.g., Pagan and Wiccan spiritualities) have been described as more affirmative toward gay, lesbian, bisexual, and transgendered (GLBT) members than mainstream Judeo-Christian faiths, but no research has explored Earth-spirited faiths' GLBT-affirming behaviors. This study investigated those behaviors as well as the faith experiences of GLBT Earth-spirited individuals. At time of coming out, participants who were affiliated with mainstream Judeo-Christian faiths reported greater faith conflict than those affiliated with Earth-spirited faiths; however, there were no differences in resolution of the conflict between the two groups, internalized homonegativity, or self-acceptance. In addition, Earth-spirited faiths engaged in many GLBT-affirming behaviors.  相似文献   
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