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71.
A problem of using a non‐convex penalty for sparse regression is that there are multiple local minima of the penalized sum of squared residuals, and it is not known which one is a good estimator. The aim of this paper is to give a guide to design a non‐convex penalty that has the strong oracle property. Here, the strong oracle property means that the oracle estimator is the unique local minimum of the objective function. We summarize three definitions of the oracle property – the global, weak and strong oracle properties. Then, we give sufficient conditions for the weak oracle property, which means that the oracle estimator becomes a local minimum. We give an example of non‐convex penalties that possess the weak oracle property but not the strong oracle property. Finally, we give a necessary condition for the strong oracle property.  相似文献   
72.
73.
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   
74.
With competing risks data, one often needs to assess the treatment and covariate effects on the cumulative incidence function. Fine and Gray proposed a proportional hazards regression model for the subdistribution of a competing risk with the assumption that the censoring distribution and the covariates are independent. Covariate‐dependent censoring sometimes occurs in medical studies. In this paper, we study the proportional hazards regression model for the subdistribution of a competing risk with proper adjustments for covariate‐dependent censoring. We consider a covariate‐adjusted weight function by fitting the Cox model for the censoring distribution and using the predictive probability for each individual. Our simulation study shows that the covariate‐adjusted weight estimator is basically unbiased when the censoring time depends on the covariates, and the covariate‐adjusted weight approach works well for the variance estimator as well. We illustrate our methods with bone marrow transplant data from the Center for International Blood and Marrow Transplant Research. Here, cancer relapse and death in complete remission are two competing risks.  相似文献   
75.
This paper deals with the problem of predicting the real‐valued response variable using explanatory variables containing both multivariate random variable and random curve. The proposed functional partial linear single‐index model treats the multivariate random variable as linear part and the random curve as functional single‐index part, respectively. To estimate the non‐parametric link function, the functional single‐index and the parameters in the linear part, a two‐stage estimation procedure is proposed. Compared with existing semi‐parametric methods, the proposed approach requires no initial estimation and iteration. Asymptotical properties are established for both the parameters in the linear part and the functional single‐index. The convergence rate for the non‐parametric link function is also given. In addition, asymptotical normality of the error variance is obtained that facilitates the construction of confidence region and hypothesis testing for the unknown parameter. Numerical experiments including simulation studies and a real‐data analysis are conducted to evaluate the empirical performance of the proposed method.  相似文献   
76.
Despite evidence that individuals with schizophrenia spectrum disorders experience significant and persistent symptoms of anxiety, there are few reports of the use of empirically supported treatments for anxiety in this population. This article describes how we have tried to adapt mindfulness interventions to help individuals with schizophrenia who experience significant anxiety symptoms. Although mindfulness has been widely used to help individuals without psychosis, to our knowledge, this is the first study adapting it to help those with schizophrenia manage worry and stress. We provide an overview of the intervention and use an individual example to describe how our treatment development group responded. We also explore directions for future research of mindfulness interventions for schizophrenia.  相似文献   
77.
This study tested the distorted cognitions component of Hall and Hirschman's (1991) quadripartite model of sexual aggression. Men (N = 107) with and without hostile sexual beliefs viewed erotic slides with a female partner who provided one of four patterns of feedback: clear disinterest, token disinterest, compliant interest, and clear interest. Hostile men reported fewer differences between women, were unresponsive to their partner's perceived embarrassment, and reported a consistent positive mood regardless of her feedback. Conversely, nonhostile men were more responsive to feedback, mirrored the partner's embarrassment, and experienced a less positive mood when she communicated clear disinterest in the erotica. These findings support the distorted cognitions component of the quadripartite model of sexual aggression. The authors also discuss the strengths and limitations of this study's methodology.  相似文献   
78.
There is a need to investigate novel interventions that promote worksite physical activity and wellness. OBJECTIVE: The authors' purpose in this study was to evaluate the effectiveness of a 12-week walking program supplemented with a pedometer, computer educational program, and weekly e-mails. METHODS: College faculty and staff participated in a one-group pre-posttest study to determine whether the 12-week walking intervention had an effect on body mass index (BMI), blood pressure, blood glucose, and cholesterol. The authors also determined participant-perceived wellness effects. RESULTS: The authors observed differences between baseline and follow-up in BMI (p = .024), blood glucose (p = .06), and total cholesterol (p = .09). The program had a moderate effect on fitness, mood, health awareness, nutrition, and health. CONCLUSIONS: It is incumbent that experts develop innovative worksite physical activity and wellness programs. A pedometer-monitored walking program is one way that a worksite health initiative can improve the health and wellness of its employees and simultaneously reduce health-care costs.  相似文献   
79.
To enrich an urban generalist MSW program serving a diverse aging community, an innovative approach was initiated. A team of students, faculty and a field instructor collaborated in creating and evaluating 3 sets of cross-cutting thematic modules. An overview of the thematic modules (addressing elder abuse, family caregiving, and mental health), integrated across multiple curriculum areas (Human Behavior and the Social Environment, Macro/Policy, Practice and Research), is presented along with results of a faculty focus group evaluating the process of coordinating module content for one full week of class per foundation area (one topic per quarter).  相似文献   
80.
This study examined the prevalence of workplace flexibility and the mechanisms that allow workplace flexibility to influence turnover intentions through work–family and family–work conflicts and job satisfaction among low‐wage workers in South Korea. Participants included 250 low‐wage workers whose monthly salary was less than 2 million Korean won (approx. $1,900). The study results indicate that low‐wage workers have limited access to workplace flexibility and that workplace flexibility plays a significant protective role in reducing their turnover intention, indirectly by decreasing work–family conflicts and enhancing job satisfaction. This article also discusses the implications of these findings for labor policy and social work practice.  相似文献   
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