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1.
Journal of Nonverbal Behavior - Age-related deficits are often observed in emotion categorization tasks that include negative emotional expressions like anger, fear, and sadness. Stimulus... 相似文献
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Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time. 相似文献
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As important members of research teams, statisticians bear an ethical responsibility to analyze, interpret, and report data honestly and objectively. One way of reinforcing ethical responsibilities is through required courses covering a variety of ethics-related topics at the graduate level. We assessed ethics requirements for graduate-level statistics training programs in the United States for the 2013–2014 academic year using the websites of 88 universities, examining 103 biostatistics programs, and 136 statistics degree programs. We categorized programs’ ethics training requirements as required or not required. Thirty-one (35.1%) universities required an ethics course for at least some degree students. Sixty-two (25.5%) degree programs required an ethics course for at least some students. The majority (77.4%) of required courses were worth 0 or 1 credit. Of the 177 programs without an ethics requirement, 19 (10.7%) listed an ethics elective. Although a single ethics course is insufficient for instilling an ethical approach to science, degree programs that model expectations through coursework point to the value of ethics in science. More training programs should prepare statisticians to consider the ethical dimensions of their work through required coursework. Supplementary materials for this article are available online. 相似文献
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Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study. 相似文献
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Schmidt Philip R. 《Sociological Practice: A Journal of Clinical and Applied Sociology》2002,4(3):195-208
The historical relationship between the electoral college and controversial U.S. presidential elections, specifically with respect to conflict, is examined. The elections of 1800, 1824, 1860, 1876, 1888, 1968, and 2000 are examined. Aside from the 2000 election, there has been essentially no conflict in American history due to the electoral college. The constitutional structure and thinking behind the form of the electoral college is given, with emphasis on the federal aspects of the structure. The current movement to abolish the electoral college in favor of direct popular vote is depicted, along with the arguments against making that change. The conclusion is that we as a nation are far better off to retain the status quo than to make the called-for change. 相似文献
7.
The authors examined the impact of sense of coherence on the career thought processes of a sample of college students. A. Antonovsky (1987) defined sense of coherence as the global orientation that the world is comprehensible, manageable, and meaningful. Study participants completed the Sense of Coherence Scale (A. Antonovsky, 1987) and the Career Thoughts Inventory (CTI; J. P. Sampson, G. W. Peterson, J. G. Lenz, R. C. Reardon, & D. E. Saunders, 1996). Multivariate tests indicated a medium relationship between sense of coherence and CTI Total and subscale scores; sense of coherence accounted for 14% of the variance. Univariate tests also indicated a medium relationship between sense of coherence and each subscale. 相似文献
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Dina M. Carbonell Helen Z. Reinherz Rose M. Giaconia Cecilia K. Stashwick Angela D. Paradis William R. Beardslee 《Child and Adolescent Social Work Journal》2002,19(5):393-412
In a longitudinal, community-based study, adolescent protective factors for those at risk for depression were identified that were associated with resilient outcomes in young adulthood. For those with childhood risk factors for major depression, significant protective factors included family cohesion, positive self appraisals, and good interpersonal relations. Findings may help inform the development of prevention and treatment programs for adolescents vulnerable to depression. Implications for future research and clinical practice are discussed. 相似文献
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