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91.
Cyber counseling is a new and growing medium for offering mental health services to children and youth. However, there is a lack of identification of the core competencies required to provide effective online counseling. A school of social work, in partnership with a national service agency providing online counseling to children and youth, developed and offered a 13-week course to participating MSW social work students and agency staff. The development of online counseling competencies was assessed through individual interviews with participants and a content analysis of online posts. Participants scored well in areas of assessment and intervention. Challenges were identified in relationship building within an online environment.  相似文献   
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The literature on testing the unit root hypothesis in the presence of GARCH errors is extended. A new test based upon the combination of local-to-unity detrending and joint maximum likelihood estimation of the autoregressive parameter and GARCH process is presented. The finite sample distribution of the test is derived under alternative decisions regarding the deterministic terms employed. Using Monte Carlo simulation, the newly proposed ML t-test is shown to exhibit increased power of relative to rival tests. Finally, the empirical relevance of the simulation results is illustrated via an application to real GDP for the UK.  相似文献   
95.
Estimating potential health risks associated with recycled (reused) water is highly complex given the multiple factors affecting water quality. We take a conceptual model, which represents the factors and pathways by which recycled water may pose a risk of contracting gastroenteritis, convert the conceptual model to a Bayesian net, and quantify the model using one expert's opinion. This allows us to make various predictions as to the risks posed under various scenarios. Bayesian nets provide an additional way of modeling the determinants of recycled water quality and elucidating their relative influence on a given disease outcome. The important contribution to Bayesian net methodology is that all model predictions, whether risk or relative risk estimates, are expressed as credible intervals.  相似文献   
96.
Progressive multi-state models provide a convenient framework for characterizing chronic disease processes where the states represent the degree of damage resulting from the disease. Incomplete data often arise in studies of such processes, and standard methods of analysis can lead to biased parameter estimates when observation of data is response-dependent. This paper describes a joint analysis useful for fitting progressive multi-state models to data arising in longitudinal studies in such settings. Likelihood based methods are described and parameters are shown to be identifiable. An EM algorithm is described for parameter estimation, and variance estimation is carried out using the Louis’ method. Simulation studies demonstrate that the proposed method works well in practice under a variety of settings. An application to data from a smoking prevention study illustrates the utility of the method.  相似文献   
97.
Services comprise an ever-expanding source of employment in the world's economies and are of significant interest to both academicians and practitioners. In this study, historical perspectives from which to view service typologies are provided and four decades of service typologies are chronicled. The interest in services demonstrated by academicians is tracked over time as are the purposes for which typologies have been developed. A unified schematic representation of services is developed in which the common themes underlying service typology development are identified from both a macro and micro level. Based on this study, areas for future research are identified.  相似文献   
98.
In the analysis of recurrent events where the primary interest lies in studying covariate effects on the expected number of events occurring over a period of time, it is appealing to base models on the cumulative mean function (CMF) of the processes (Lawless & Nadeau 1995). In many chronic diseases, however, more than one type of event is manifested. Here we develop a robust inference procedure for joint regression models for the CMFs arising from a bivariate point process. Consistent parameter estimates with robust variance estimates are obtained via unbiased estimating functions for the CMFs. In most situations, the covariance structure of the bivariate point processes is difficult to specify correctly, but when it is known, an optimal estimating function for the CMFs can be obtained. As a convenient model for more general settings, we suggest the use of the estimating functions arising from bivariate mixed Poisson processes. Simulation studies demonstrate that the estimators based on this working model are practically unbiased with robust variance estimates. Furthermore, hypothesis tests may be based on the generalized Wald or generalized score tests. Data from a trial of patients with bronchial asthma are analyzed to illustrate the estimation and inference procedures.  相似文献   
99.
This two-wave longitudinal study examined peer selection and influence pertaining to tobacco and alcohol use by adolescents and their friends in a sample of 854 Chinese adolescents (384 girls: mean age = 13.33 years). Participants nominated friends and self-reported their tobacco and alcohol use at seventh and again at eighth grade. Longitudinal social network analyses revealed evidence of friend influence but not selection over smoking and drinking. Boys increased their levels of smoking at rates greater than that of girls, but no sex moderation of either selection or influence was found. In interpreting these results, it is important to understand the gender norms for Chinese boys and girls and the cultural context of tobacco and alcohol use.  相似文献   
100.
Jogging is a relatively under-researched mobile practice with much existing literature focusing on ‘serious’ and competitive running. In this paper, we provide an account of some of the movements, meanings and experiences that together help produce the practice of jogging in the south-western English city of Plymouth. Drawing upon participant diaries and interviews, we uncover rich detail about how joggers ascribe not one but a number of meanings to their practice. Some of these are positive, some are negative; some complement each other and some compete with each other. We also consider how the experiences of joggers can be shaped by their ongoing need to develop tactics capable of enabling them to negotiate space with non-joggers. This is in some contrast to more competitive running that occurs in the separated space of an athletics track. Our sense is that better awareness of the meanings and experiences of jogging will be of value if the advertised health and sustainability benefits of the practice are to be more effectively encouraged and promoted.  相似文献   
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