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941.
In this article we show that optimistic financial expectations impact positively on both the quantity of debt and the growth in debt at the individual and household levels. Our theoretical model shows that this association is predicted under a variety of plausible scenarios. In the empirical analysis we explore the determinants of debt and of growth in debt using British data. We find convincing support for our theoretical priors and show that it is optimistic financial expectations per se that are important in influencing debt, rather than the accuracy of individuals' predictions regarding their future financial situation.  相似文献   
942.
This article presents the qualitative findings from a larger mixed methods study of the barriers and costs associated with disability in New Zealand. A social model of disability framework was integrated with an economic cost model using consensual budget standards to (1) identify key barriers disabled people experience in their everyday living and (2) develop consensus about the resources disabled people agree they require to reduce or remove them. Forty-nine people with physical, hearing, vision or intellectual impairment participated in a series of 8 impairment-based focus groups. The analysis identified inaccessible environments, negative attitudes, unreliable transportation and poor access to information as key barriers. However, lack of adequate and appropriate resources (e.g. equipment, modifications, support, transport and time) to address these barriers was the overarching obstacle to participation. The inclusion of time as both a barrier and a valuable resource is arguably the most important contribution of the study.  相似文献   
943.
Mediation analysis often requires larger sample sizes than main effect analysis to achieve the same statistical power. Combining results across similar trials may be the only practical option for increasing statistical power for mediation analysis in some situations. In this paper, we propose a method to estimate: (1) marginal means for mediation path a, the relation of the independent variable to the mediator; (2) marginal means for path b, the relation of the mediator to the outcome, across multiple trials; and (3) the between-trial level variance–covariance matrix based on a bivariate normal distribution. We present the statistical theory and an R computer program to combine regression coefficients from multiple trials to estimate a combined mediated effect and confidence interval under a random effects model. Values of coefficients a and b, along with their standard errors from each trial are the input for the method. This marginal likelihood based approach with Monte Carlo confidence intervals provides more accurate inference than the standard meta-analytic approach. We discuss computational issues, apply the method to two real-data examples and make recommendations for the use of the method in different settings.  相似文献   
944.
This is one of the first qualitative event-based studies to understand the various mechanisms through which multiple factors influence condom use decision making among homeless youth. Event-level interviews that explore characteristics of the environment surrounding sexual events were conducted with 29 youth who were asked to describe two recent sexual encounters. In thematic analyses of data across events, reasons that youth gave for engaging in unprotected sex included the expectation of having sex and use of alternative methods of protection against pregnancy. Other nonevent factors that influenced condom use decision making were related to attributes of the partnership (e.g., testing, trust and love, and assessments of risk) and attributes of the youth (e.g., perceptions of diseases, concerns over pregnancy, and discomfort using condoms). Additional event analyses conducted within the same individuals found that decision making was influenced by multiple interacting factors, with different pathways operating for event and nonevent factors. Future interventions should consider taking a multilevel and individualized approach that focuses on event-based determinants of risky sex in this population.  相似文献   
945.
946.
The multiple‐family group intervention is an effective, yet affordable, 8‐week treatment that is conducted in a juvenile correctional institution in Alabama with adolescents who sexually offend and their families. Data from 115 incarcerated male adolescents and their male and female caregivers collected at pre‐, post‐, and 1‐year follow‐up were used to determine that problem behaviors (internalizing, externalizing) decreased over pre‐ and posttest and the significant decreases in maladaptive emotion regulation predicted those changes. Adolescent‐reported anxiety over abandonment and attachment dependence on parents increased significantly; these changes were predicted by decreases in maladaptive emotion regulation. Linear growth models were also fit over the 3 time points and indicate decreases in adolescent problem behavior and maladaptive emotion regulation.  相似文献   
947.
Each month, 200,000 widows and 6,000 widowers receive Social Security disabled widow(er)s benefits, each benefit averaging about $550. Among the most economically at-risk Social Security beneficiaries, their benefits are permanently reduced. This paper reviews the legislative history of the disabled widow(er)s benefit, identifying key decisions that gave shape to this benefit. Social Security program data and six years of Current Population Survey data (March Annual Demographic Files, 1995-2000) are used to profile the economic status of current and potential disabled widows. The analysis, including comparison with other widows, provides strong evidence of economic need among disabled widows with, for example, 44% of disabled widow beneficiaries, ages 50-59, having below-poverty incomes compared with 15% of like-aged non-disabled widows. We conclude that serious consideration should be given to extending eligibility to all widow(er)s disabled before the normal retirement age; to providing a benefit equal to 100% of the deceased spouse's private insurance amount (PIA); to eliminating the unnecessarily restrictive seven-year rule; and to protecting beneficiaries from losing their eligibility to Medicaid. Even in the context of today's heated Social Security debate, we suggest that a rare opportunity may exist to garner bipartisan support for meaningful, low-cost improvements, in a benefit that primarily targets women.  相似文献   
948.
949.
We show that Stein's phenomenon is impossible for the following decision setting: the parameter space is compact, the loss function is the sum of coordinatewise strictly convex continuous loss functions, and the probability density function having the same support for every parameter θ is continuous in θ. Therefore, any coordinatewise admissible decision rule is admissible.  相似文献   
950.
One of the most effective ways to describe the successional gradient of an environment is by using measures of biodiversity. We investigated the biodiversity of ant communities (known tramp/structure invaders) in an environment undergoing urban succession to characterize how ant communities changed along a disturbance gradient. Ant community dynamics were examined within three Puerto Rican housing developments of different ages. Within each development, we assessed the ant community using biodiversity measures of richness, abundance, diversity and evenness. We also studied changes in biodiversity within each development over time as well as how biodiversity related to food preferences within the ant communities. In general, the biodiversity measures increased as the age of the housing development increased. Monthly changes in biodiversity indicated that month was a better predictor of biodiversity in the most recently disturbed development, while the biodiversity in the older developments was less predictable from month to month. The biodiversity measures also suggested that the ant community in the youngest development was comprised mostly of generalist feeders. However, the older sites’ ant species appeared to have more specific feeding preferences. Based on the biodiversity measures of these ant communities, our findings suggest that the housing developments of different ages represented advancing stages of secondary succession. Furthermore, this study indicated that the succession of ant species occurs rapidly (<10 years) in urban environments, resulting in a relatively diverse ant community.  相似文献   
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