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991.
ABSTRACT African American adolescents continue to be disproportionately impacted by HIV, sexually transmitted infections (STIs), and unanticipated pregnancies. In-depth, face-to-face interviews among a convenience sample of 32 African American adolescents (16 male and 16 female) were used to explore the reasons why some adolescents decided to engage in sex while others chose to delay sexual debut. Data were analyzed using a thematic analysis. Among the overall sample, psychological motivations, external pressure, physical pleasure seeking, and relationship-related motivations were the major themes cited for engaging in sex by participants and their friends. External support, motivation to avoid negative consequences, not feeling ready or lacking interest in sex, and having negative views about sex were among the major reasons for delaying sex. Several of the emergent themes showed gender differences. Suggestions for future research include the need for sexual education, and STI/HIV prevention programs that are gender sensitive and flexible enough to accommodate multiple factors related to sexual debut. 相似文献
992.
M. Safiul Haq 《统计学通讯:理论与方法》2013,42(9):857-866
The location-scale model with equi-correlated responses is discussed. The structure of the location-scale model is utilised to genera-te the prediction distribution of a future response and that of a set of future responses. The method avoids the integration procedures usually involved in derivation of prediction distributions and yields results same as those obtained by the Bayes method with the vague prior distribution* Finally the re-suits have been specialised to cover the case of the normal intra-class model. 相似文献
993.
Loretta M. Kopelman 《Accountability in research》2013,20(3-4):177-192
The Maryland Court of Appeals in Grimes v. Kennedy Krieger Institute was sharply critical of the lead abatement study conducted by this Institute, an affiliate of Johns Hopkins University. Grimes ruled that investigators might, given the facts of the case, have a special relationship with subjects, thereby creating a duty of care that could, if breached, give rise to an action in negligence. This ruling has implications for pediatric research practices and long-standing disputes among informed people of good will about what pediatric studies should be permitted. 相似文献
994.
Ruth M. Mickey 《统计学通讯:理论与方法》2013,42(3):755-759
For a large series of IxJ tables, each containing two observations, the bias of the maximum likelihood estimates of log linear partial association parameters is shown to be equal to the parameters, regardless of the size of I and J. The partial association considered is that between row and column variables; the three way interactions are assumed to be O. This is a generalization of Andersen's results (1973a, 1973b) for a series of 2x2 tables. 相似文献
995.
N. Mukhopadhyay 《统计学通讯:理论与方法》2013,42(8):2471-2506
The literature on sequential estimation problems for negative exponential populations has been reviewed here, We attempt to bring in all the published and unpublished materials known to us in a fairly coherent fashion. Both the concepts and theoretical findings are discussed. 相似文献
996.
997.
Annelies E. M. van Vianen Irene E. De Pater Paul T. Y. Preenen 《The Career development quarterly》2009,57(4):298-309
Today, young adults are expected to decide between educational, vocational, and job options and to make the best choice possible. Career literatures emphasize the importance of young adults' career decision making but also acknowledge the problems related to making these decisions. The authors argue that career counselors could support clients' intuitive processing of career information and help their clients to develop a positive and flexible view of the self and the environment while diminishing concerns about accountability for and irreversibility of career decisions. The authors argue that career adaptability rather than decision making should become the focal concept of career theory and practice. 相似文献
998.
999.
ABSTRACTOn the basis of Csiszar's φ-divergence discrimination information, we propose a measure of discrepancy between equilibriums associated with two distributions. Proving that a distribution can be characterized by associated equilibrium distribution, a Renyi distance of the equilibrium distributions is constructed that made us to propose an EDF-based goodness-of-fit test for exponential distribution. For comparing the performance of the proposed test, some well-known EDF-based tests and some entropy-based tests are considered. Based on the simulation results, the proposed test has better powers than those of competing entropy-based tests for the alternatives with decreasing hazard rate function. The use of the proposed test is evaluated in an illustrative example. 相似文献
1000.
Bailey has shown that choice of certain trigonometlk levels for factors in a symmetrical confounded factorial design is more efficient for quantitative treatments. This paper introduces certain incidence matrices associated with the flats of different pencils of such designs to obtain an explicit expression for the efficiency and also gives a simpler derivation of Bailey's results. 相似文献