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101.
Predicting Adolescents' Initiation of Intercourse and Contraceptive Use   总被引:1,自引:0,他引:1  
This paper examines whether variables consistent with problem behavior theory predict grade of onset of first intercourse and adoption of effective contraception. A total sample of 3,419 Wisconsin adolescents in Grades 7, 9, and 11 participated in a survey of health-related behaviors administered 3 times across a 6-year period. The sample is 87% White. Multiple regression methods generated different models for onset of sexual intercourse vs. contraceptive adoption. Consistent with problem behavior theory, sexual onset is predicted by the adolescent's behavioral system, perceived peer substance use/abuse, importance of friends, and extent to which the adolescent felt harried and believed it was okay to break laws. Contraceptive adoption is predicted by family structure, socioeconomic variables, and self-esteem. Age and gender model differences emerged.  相似文献   
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The present study examined the validity of the Social Problem-Solving Inventory (SPSI) and SPSI—Revised in differentiating 65 high-suicidal from 63 depressed, low-suicidal college students. Results from multivariate analyses indicated overall differences in problem-solving between these two groups as measured by the SPSI but not by the SPSI-R. Further examination of these differences revealed the high-suicidal group was different in problem-solving orientation, rather than problem-solving skills, compared to the depressed, low-suicidal group. However, when depression was statistically controlled in hierarchical regression analyses, none of the problem-solving measures predicted group membership. The superiority of the SPSI to the SPSI-R in differentiating these two groups appears to be accounted for by the elimination of 28 items in the revised version, many of which measure orientation to problem-solving. Also explored was the possibility that objective measures of problem-solving provide a better prediction of adjustment than do self-report measures.  相似文献   
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Abstract— When two shapes that differ in orientation or size have to be compared or objects have to be recognized from different viewpoints, the response time and error rate art systematically affected by the size of the geometric difference. In this report, we argue that these effects are not necessarily solid evidence for the use of mental transformations and against the use of invariants by the visual system. We report an experiment in which observers were asked to give affine-invariant coordinates of a point located in an affine frame defined by three other points. The angle subtended by the coordinate axes and the ratio of the lengths of their unit vectors systematically affected the measurement errors. This finding demonstrates that the visual system's measurement of invariants need not itself be invariant.  相似文献   
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This report explores the relationship between philosophy and medicine in the Netherlands. In Section 1 we outline the ups and downs of medico-philosophical research in our country: pre-war flourishing, post-war decline, and modern renaissance. In Section 2 we review recent Dutch literature in the philosophy of medicine. The topics dealt with include methodology of medical science, alternative medicine, the basic concepts of medicine, anthropological medicine, medicalization, medicine and culture, and health care ethics.  相似文献   
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A new computational method to fit the weighted euclidean distance model   总被引:1,自引:0,他引:1  
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper.  相似文献   
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