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31.
A new method is proposed for estimating factor means and factor covariances in a group of individuals selected on their observed scores. The selection variable is, for example, the total score on an admissions test. Given a factor model for the test items based on the group of test takers, we may be interested in the factor structure for those in the top quartile. The differences in factor means and covariances between this selected group and the full group gives useful information both on successful test performance and on test validity. The new method draws on the classic Pearson-Lawley selection formulas. It avoids the fallacy of factor analysis on the selected group, which would lead to incorrect estimates. The new method is applied to a simple factor structure model for the GMAT test. Although the majority of the GMAT items test verbal skills, it is found that a quantitative factor shows the greatest change in moving from average to top quartile test takers.  相似文献   
32.
The purposes of this study were (a) to examine the role of social evaluative concerns in the self-report of sympathy and in the relation of sympathy to helping; and (b) to determine the role of "altruistic personality" traits and situationally induced vicarious emotional responses in the intention to help. Dispositional and situational self-reports of sympathy and other vicarious emotional reactions were obtained for persons who also were given the opportunity to assist a needy other. Moreover, dispositional measures of concern with social evaluation and an altruistic orientation were obtained, and a bogus pipeline manipulation was instituted for half the study participants. Both dispositional and situational self-reported sympathy were positively related to helping, as were other personality indices viewed as reflecting altruistic characteristics. The relations for the dispositional indices of sympathy were not due solely to social evaluative concerns or to other egoistic concerns. The effects on intended helping of dispositional sympathy, perspective taking, and the tendency to ascribe responsibility for others to the self appeared to be both direct and mediated by situational sympathetic responding. Finally, situational sadness did not mediate the effects of sympathetic responsiveness.  相似文献   
33.
The author diagnoses 350 carefully selected schizophrenic subjects, their parents and their siblings during parallel studies using three different clinical classification systems and analyzes the results by multiple threshold analysis and the multifactorial inheritance model. The results suggest that, of the three classifications the author studied, Leonhard's and Sneshnewski's system yield relatively homogeneous subgroups; this indicates the future significance of these nosological systems for the planning of biopsychiatric research.  相似文献   
34.
Some features of social living were investigated in three inbred strains of mice: C57Bl/6j, Balb/cj, and NIH. Five social behaviors--Aggression, Submission, Allogrooming, Social Rest and Rest Alone, as well as Wheel Running Activity--were recorded 2 h daily for a week, in 26 groups of seven male mice living in an enriched environment. Dominants and subordinates among strains shared some behavioral characteristics, but strain contributions upon social structure were also detected. Similarities among strains included the appearance of a single dominant mouse per group rated as the most aggressive, besides from being the animal presented with most Submissions. Allogrooming was more frequent among subordinates than among dominants and subordinates. Differences among strains were that agonistic behavior among subordinates was higher in the Balb/cj and NIH groups than in the C57Bl/6j mice. NIH mice were recorded in Rest Alone more often than mice from the other strains. C57Bl/6j dominants showed higher rates of Wheel Running Activity than subordinates.  相似文献   
35.
A general latent variable model is given which includes the specification of a missing data mechanism. This framework allows for an elucidating discussion of existing general multivariate theory bearing on maximum likelihood estimation with missing data. Here, missing completely at random is not a prerequisite for unbiased estimation in large samples, as when using the traditional listwise or pairwise present data approaches. The theory is connected with old and new results in the area of selection and factorial invariance. It is pointed out that in many applications, maximum likelihood estimation with missing data may be carried out by existing structural equation modeling software, such as LISREL and LISCOMP. Several sets of artifical data are generated within the general model framework. The proposed estimator is compared to the two traditional ones and found superior.The research of the first author was supported by grant No. SES-8312583 from the National Science Foundation and by a Spencer Foundation grant. We wish to thank Chuen-Rong Chan for drawing the path diagram.  相似文献   
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37.
In this paper, we present a BASIC program for Apple II series computers that allows the user to obtain perspective drawings of two-dimensional functions of known analytical expression. Also, we outline a procedure for obtaining perspective representations of two-dimensional arrays of data using the same program. The program should run on any computer with graphics mode with only slight modifications in the graphics commands.  相似文献   
38.
The authors sum up the most important basic principles of diagnostics and genetics of the schizophrenic psychoses from the viewpoint of genetic counseling for the practising psychiatrist and medical geneticist. Regarding genetic counselling strategy, in addition to nosological considerations, they stress the importance of socio-cultural and social psychological factors and of the emotional atmosphere in the family, which should all be taken into account together. Because of the special situation of schizophrenic (and in general, psychiatric) patients and their families, they regard it as advisable to set up a separate psychiatric genetic counselling service.  相似文献   
39.
Earlier work on the quality of care in settings for severely and profoundly mentally-handicapped adults raised the question whether any useful purpose is served by promoting the extensive use of simple recreational materials to occupy people. Data were collected by direct observation on the activity of 6 adults living in a staffed house organized to promote engagement in household activities. Observations were taken over 5 weekdays from 07.00 to 10.00 and 15.00 to 23.00hr. The results showed that Ss spent between 22 and 67% of available time in purposeful activity. Between 27 and 65% of purposeful activity was engagement in domestic or housework tasks. Even the most handicapped people spent more time engaged in housework than in leisure and recreational tasks. The implications of these data are commented on and measurement issues which arise in ordinary housing as opposed to institutional settings are discussed.  相似文献   
40.
A questionnaire was developed to measure beliefs about and experiences with violence in the family. Two groups of persons in two different states who had attended conferences on battered women participated in this research. Of the 177 subjects (84% women, 16% men), none of the men had been battered, yet over one-third of the women had been; more older women reported having been adult battering victims than did younger women; the women had less formal education than the men; the women in the lower educational groups were more likely to have been battered and to report fear of becoming victims; and the social service workers reported little fear of battering.  相似文献   
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