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1.
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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The voluntary nonprofit sector in Ireland has grown significantly in recent years. A related trend has been the growth of cross‐border (in effect, transnational) cooperation between voluntary organizations based in Northern Ireland and the Republic of Ireland. However, this development has posed a set of management issues in terms of structure, forms of governance and decision making, day‐to‐day project management, and sustainability. Cross‐border work has also meant that voluntary bodies confront a distinctive set of barriers in relation to political and ethnic conflict, social and cultural attitudes, and practical delivery. Strengthening of cooperation across borders will require greater planning, mainstream funding, focused management, diversification of services, and realistic expectations.  相似文献   
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The Analysis of Verbal Behavior - Participants first became familiar with an image showing moderate symptoms of the skin cancer melanoma. In a generalization test, they indicated whether images...  相似文献   
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Abstract

Objective: The purpose of this study was to examine the drinking patterns of club and intramural college athletes and compare their alcohol consumption, perceived norms around the excessive use of alcohol, experience of negative consequences, and employment of protective strategies with those of campus varsity athletes. Participants: A total of 442 undergraduate students attending a private, suburban institution in the Northeast participated in the American College Health Association National College Health Assessment-II Web survey in spring 2011. Thirty-five students identified themselves as varsity athletes, 76 identified as club sport athletes, and 196 students identified themselves as intramural athletes. Methods: Survey responses were analyzed using Statistical Package for the Social Sciences. The Pearson's correlation coefficient and test for independence were applied to identify significant relationships between athlete status and identified variables related to alcohol use. Results: Results indicated that there were significant correlations between athlete status and all variables, to varying degrees. Conclusions: These findings have implications for campus health promotion professionals and athletics program coordinators seeking to address high-risk alcohol use among college athletes.  相似文献   
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Abstract

The authors examined a proposed profile of eating-related behaviors, associated features, developmental issues, and help-seeking behavior among college women, using an eating disorder response program. The most common symptom scenario was a pattern of regular binge eating, together with daily exercise and occasional purging. The most common associated features were distressing or dysfunctional overconcern about body image and self-esteem, usually with day-to-day stress and intermittent depression. The women who fit this pattern also presented developmental issues of perfectionism, conflictual relationships with parents, and struggles for independence; and they tended to be ambivalent about seeking services. Implications for practice, including the need to develop a framework for eating disorder responses on campus that includes preventive programs and developmental interventions to target emerging and moderate concerns are discussed; limitations and the preliminary nature of the findings are explicated.  相似文献   
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Techniques used in variability assessment are subsequently used to draw conclusions regarding the “spread”/uniformity of data curves. Due to the limitations of these techniques, they are not adequate for circumstances where data manifest with multiple peaks. Examples of these manifestations (in three-dimensional space) include under-foot pressure distributions recorded for different types of footwear (Becerro-de-Bengoa-Vallejo et al., 2014 Biau, D.J. (2011). In brief: Standard deviation and standard error. Clinical Orthopaedics and Related Research 469(9):26612664.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]; Cibulka et al., 1994 Cibulka, M.T., Sinacore, D.R., Mueller, M.J. (1994). Shin splints and forefoot contact running: A case report. Journal of Orthopaedic &; Sports Physical Therapy 20(2):98102.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]; Davies et al., 2003 Davies, M.B., Betts, R.P., Scott, I.R. (2003). Optical plantar pressure analysis following internal fixation for displaced intra-articular os calcis fractures. Foot &; Ankle International 24(11):851856.[PubMed], [Web of Science ®] [Google Scholar]), surface textures and interfaces designed to impact friction, and and and molecular surface structures such as viral epitopes (Torras and Garcia-Valls, 2004 Torras, C., Garcia-Valls, R. (2004). Quantification of membrane morphology by interpretation of scanning electron microscopy images. Journal of Membrane Science 233(1–2):119127.[Crossref], [Web of Science ®] [Google Scholar]; Pacejka, 1997; Fustaffson, 1997). This article proposes a technique for generating a single variable – Λ that will quantify the uniformity of such surfaces. We define and validate this technique using several mathematical and graphical models.  相似文献   
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