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901.
902.
A fast and accurate method of confidence interval construction for the smoothing parameter in penalised spline and partially linear models is proposed. The method is akin to a parametric percentile bootstrap where Monte Carlo simulation is replaced by saddlepoint approximation, and can therefore be viewed as an approximate bootstrap. It is applicable in a quite general setting, requiring only that the underlying estimator be the root of an estimating equation that is a quadratic form in normal random variables. This is the case under a variety of optimality criteria such as those commonly denoted by maximum likelihood (ML), restricted ML (REML), generalized cross validation (GCV) and Akaike's information criteria (AIC). Simulation studies reveal that under the ML and REML criteria, the method delivers a near‐exact performance with computational speeds that are an order of magnitude faster than existing exact methods, and two orders of magnitude faster than a classical bootstrap. Perhaps most importantly, the proposed method also offers a computationally feasible alternative when no known exact or asymptotic methods exist, e.g. GCV and AIC. An application is illustrated by applying the methodology to well‐known fossil data. Giving a range of plausible smoothed values in this instance can help answer questions about the statistical significance of apparent features in the data.  相似文献   
903.
In this article, we investigate the potential usefulness of the three-parameter transmuted generalized exponential distribution for analyzing lifetime data. We compare it with various generalizations of the two-parameter exponential distribution using maximum likelihood estimation. Some mathematical properties of the new extended model including expressions for the quantile and moments are investigated. We propose a location-scale regression model, based on the log-transmuted generalized exponential distribution. Two applications with real data are given to illustrate the proposed family of lifetime distributions.  相似文献   
904.
Under appropriate long range dependence conditions, the point process of exceedances of a stationary sequence weakly converges to a homogeneous compound Poisson point process. This limiting point process can be characterized by the extremal index and the cluster-size probabilities. In this paper we address the problem of estimating these quantities and we consider the intervals estimators introduced in Ferro and Segers [2003. Inference for clusters of extreme values. J. Roy. Statist. Soc. Ser. B 545–556] and in Ferro [2004. Statistical methods for clusters of extreme values. Ph.D. Thesis, Lancaster University]. We establish asymptotic weak convergence to Gaussian random variables and we give their asymptotic variance.  相似文献   
905.
Adolescent parenthood has highly publicized adverse social and economic consequences, but these same social and economic disadvantages can be viewed as root causes of adolescent pregnancy. Recent research and revisionist debates about these issues are reviewed and summarized. Diverse implications for social policy are considered. Prevention approaches are emphasized that build on both postponing adolescent sexual intercourse and helping sexually active teens avoid pregnancy.Appreciation is expressed to Christine Bachrach and Kristin Moore for their comments on a previous version of this paper.Dr. Miller's current research interests are the family antecedents of adolescent sexual behavior and the design and evaluation of prevention programs for adolescent problem behaviors. He received his Ph.D. in family sociology from the University of Minnesota in 1975.  相似文献   
906.
Social workers are often challenged by the complex and ever‐changing dynamics within their relationships with clients, and struggle to find ethical responses within professional boundary grey zones where boundaries with clients can be difficult to identify, yet easy to cross. Social work educators attempt to prepare students for these complex situations, yet in the United States research reveals rates of social work boundary violations that lead one to question the efficacy of social work ethics education. This article describes the educational competencies and instructional strategies that comprise an adaptable course module which was developed in response to this challenge, and intended to increase students' self‐awareness, motivation and professional judgment‐making abilities related to their professional boundaries. The educational competencies for this course include the abilities to: identify boundary violations, apply critical thinking skills to complex professional relationship contexts, increase awareness of self and other, and initiate prevention strategies. In contrast to traditional approaches to education, this article describes instructional strategies that are based on adult‐learning principles, which have the purpose of effectively and creatively teaching topic areas in such a way as to produce behavioural change. These course topic areas include a ‘Professional Relationship Boundaries Continuum’ conceptual framework, boundary violation impacts, personal boundary vulnerabilities, blurring boundary indicators, and risk‐minimizing strategies.  相似文献   
907.
908.
Routinely collected computerized data were used to study the process of service delivery in terms of admission patterns, type and quantity of services rendered, and status at termination for whites and nonwhites in two community mental health centers. Social area analysis techniques were employed to control for socio-economic status, ethnicity and life style variables, and an epidemiologic model was used to analyze admission and service delivery rate differences. It was found that nonwhite admission rates were at least twice as great as white rates. Service delivery rates to the population at large were considerably greater for nonwhites than for whites. Delivery of direct services within the centers differed for whites and nonwhites, but no consistent trends emerged when types and amounts of services rendered were analyzed, controlling for sex, ethnicity, age, diagnosis and social area. Disruption of care indices were greater for nonwhites than for whites. Highlighted were some of the complexities involved in interpreting results of utilization studies.  相似文献   
909.
It has been demonstrated that sexual minority men (SMM) participate in sexting. While research has shown that engagement in the exchange of sexually explicit media is associated with poor health outcomes, no previous research has investigated its association with sleep health outcomes. This study sought to examine the association between sexually explicit media and sleep health among SMM, a population that suffers from poor sleep health. A popular geosocial networking application was used to recruit SMM individuals (N?=?580) in the Paris, France, metropolitan area. Multivariate analyses, adjusting for sociodemographics, were used to test the association between the frequency of sexually explicit messaging and three dimensions of sleep health: (1) sleep quality, (2) sleep duration, and (3) two aspects of sleep problems. In multivariate analyses, those who reported engaging in sexually explicit messaging more were more likely to report getting less than seven?hours of sleep (aRR = 1.24; 95% CI = 1.08, 1.43) compared with those who reported engaging in sexually explicit messaging less. No significant associations were found between sexting and sleep quality or reporting sleep problems. Sexually explicit messaging was associated with shorter sleep duration. Intervention targeted at individuals who sext could potentially improve sleep health outcomes.  相似文献   
910.
We analyse 4300 advertisements of children featured in the Today's Child column, a daily written by Helen Allen in The Toronto Telegram and The Toronto Star from 1964 to 1982, to understand how the Canadian public became accepting of the adoption of Indigenous children. While children of all ethnic backgrounds were featured, the Indigenous children who were displayed were part of a larger system of child removal, known as the ‘Sixties Scoop’. We demonstrate the ways Indigenous children are described with a specific form of happiness that is conjoined with colonial conceptions of the family and nation.  相似文献   
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