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771.
To participate or not to participate: that is the question 总被引:1,自引:0,他引:1
Borden LM Perkins DF Villarruel FA Stone MR 《New directions for youth development》2005,(105):33-49, 10
Do I wish to participate or not to participate in this program? That is the question that young people ask themselves when considering a new opportunity. What can be done to increase the likelihood that they will choose to participate in out-of-school-time (OST) programs? This chapter describes a qualitative study that examined reasons for participating or not participating in OST programs. Some common reasons emerged, but the study also revealed differences among youth from different ethnic groups. It is clear that those who design and conduct programs must understand the processes through which diverse adolescents initiate their participation in programs and either persist or drop out. Given the apparent benefits of active participation in youth programs, it is important to remove barriers and increase access and, equally important, design programs that are of interest to youth in the contexts in which they live. 相似文献
772.
Using the data from the AIDS Link to Intravenous Experiences cohort study as an example, an informative censoring model was
used to characterize the repeated hospitalization process of a group of patients. Under the informative censoring assumption,
the estimators of the baseline rate function and the regression parameters were shown to be related to a latent variable.
Hence, it becomes impractical to directly estimate the unknown quantities in the moments of the estimators for the bandwidth
selection of a smoothing estimator and the construction of confidence intervals, which are respectively based on the asymptotic
mean squared errors and the asymptotic distributions of the estimators. To overcome these difficulties, we develop a random
weighted bootstrap procedure to select appropriate bandwidths and to construct approximated confidence intervals. One can
see that our method is simple and faster to implement from a practical point of view, and is at least as accurate as other
bootstrap methods. In this article, it is shown that the proposed method is useful through the performance of a Monte Carlo
simulation. An application of our procedure is also illustrated by a recurrent event sample of intravenous drug users for
inpatient cares over time. 相似文献
773.
Gordon F. Sutton 《Demography》1977,14(4):419-430
A model is developed to use marital history data from the U.S. Current Population Survey and mortality statistics from the federal registration system to estimate color differences in (a) the risk of widowhood among women in the working ages and (b) the cumulative duration of widowhood. Color differentials in mortality among married males are thereby translated into person-years of dependent survivorship among women, in anticipation of our later estimating average and cumulative lifetime income losses for the survivors. Initial results of this model, dealing with the demographic aspects of survivorship, are presented. 相似文献
774.
Milton F. Shore 《Children and youth services review》1979,1(1):120-122
775.
C. F. Midelfort 《Journal of marital and family therapy》1982,8(2):1-11
Editor's Note. Occasionally, the Journal of Marital and Family Therapy will publish papers of major historical significance to the field of family therapy which, though written long before their appearance in the Journal, have remained unpublished and received little public circulation or attention. Such papers are those which, in the view of the Editor, would have been certain “classics” in the literature of family therapy had they been published when they were written, and which, despite their overdue appearance, are of significant enduring value. The first of these papers, by Dr. C. F Midelfort, appears here. Though essentially isolated from the family therapy movement that was soon to follow, Dr. Midelfort, in fact, published the first book on family therapy. The present article grows out of what was probably the first paper on family therapy ever presented at a psychiatric convention in the United States. In this paper, originally written almost exactly thirty years ago, Dr. Midelfort articulately presents a creative interweaving of an appreciation of the psychodynamics of family relationships with an ego-oriented family approach to severe psychiatric disturbance in one family member. It is an innovative presage of the flexible use of the principles of family dynamics, social psychiatry and biological psychiatry that has been “discovered” only very recently in family therapy with schizophrenics. The paper is introduced by Dr. John E. Bell, to whom the Journal is grateful for bringing it to light. 相似文献
776.
Recent work on extended optimality criteria for robust designs is applied to response surface problems. Methods of calculation are described and the criteria illustrated with several examples. The extended criteria discriminate among designs equivalent by other criteria. 相似文献
777.
778.
The present outcome study is a preliminary report on whether personality changes occur in parents receiving behavioral family therapy. Behavioral techniques for changing the identified patient's presenting problem were taught to the parents and each family member was given a weekly behavioral homework assignment intended to change the dysfunctional interactions assessed in the family.
An analysis of pre and post measures using Cattell's 16PF questionnaire showed a significant decrease in the parent's self-sufficiency index, indicating increased group dependence. The mean number of sessions was 12.6. The results of this study raise questions about the nature of the personality changes occurring in family therapy of this type. Family therapists, often-times assuming the role of the "expert" for the family, may be unwittingly fostering group dependence and losses in confidence for parents receiving such family guidance. 相似文献
An analysis of pre and post measures using Cattell's 16PF questionnaire showed a significant decrease in the parent's self-sufficiency index, indicating increased group dependence. The mean number of sessions was 12.6. The results of this study raise questions about the nature of the personality changes occurring in family therapy of this type. Family therapists, often-times assuming the role of the "expert" for the family, may be unwittingly fostering group dependence and losses in confidence for parents receiving such family guidance. 相似文献
779.
780.