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151.
The results of an evaluation of the perfusion scintigraphy findings of 350 hospitalised neurological patients and 55 more strictly selected neurosurgical patients with cerebrovascular complaints, revealed an accuraty of 83%, a sensitivity of 89%, and a specificity of 83%. The selection of the patients had no influence on the results as a whole. Compared with contrast-medium angiography, incorrect diagnosis must be expected in 17% of the cases. This includes erroneous negative findings in 10% of the cases. Grounds for misinterpretations are suggested, and the biological and methodological limitations of the method are set forth.  相似文献   
152.
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   
153.
The relationship between the personality components of psychoticism, extraversion and neuroticism, and levels of conduct disorder, delinquency and therapy responsiveness in children is investigated. A series of studies reporting short- and long-term results test Eysenck's (1970) argument that extraverts, because of their lower levels of conditionability, should feature more prominently in groups showing higher levels of conduct disorder or delinquency. The extension of that argument to include the role of psychoticism (Eysenck H.J. and Eysenck S.B.G., Psychoticism as a Dimension of Personality, Hodder & Stoughton, London, 1976) is also subjected to experimental test. Two alternative conceptions of the part played by neuroticism, either that it acts as an amplifying device (high N) or as a filter against pressure to change (low N), are considered. The results support the importance of including personality factors in the study of antisocial behaviour in children.  相似文献   
154.
The term pioneer is used for girls aspiring to male-dominated careers. This longitudinal study assesses the career choices of 68 middle-class girls during childhood (8–13 years, Phase I) and again during adolescence (13–18 years, Phase II), and investigates the relation between pioneering career choice and personal and family characteristics. Subjects were originally selected for exposure vs nonexposure to exogenous hormones during pregnancy. In childhood, pioneers were somewhat older, were more often persistent tomboys, had higher IQs, and had parents with higher educational attainment. In adolescence, paternal education was the only variable that showed the same relation to career choice. Adolescent girls who had wanted to get married at the time of the childhood assessment were now less likely to choose pioneering careers. Adolescent pioneers also had higher educational aspirations than nonpioneers and less likely anticipated being married within ten years than nonpioneers. A number of statistically borderline relationships were also observed: pioneers had somewhat fewer older brothers than nonpioneers, less often came from homes in which traditional femininity was stressed, and more frequently had mothers who had worked outside the home throughout their daughters' school years than mothers of nonpioneers. Prenatal exposure to exogenous sex hormones was not related to career choice during either childhood or adolescence.  相似文献   
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The purpose of this study was to examine the relationship of four client characteristics—functioning level, aggressive behavior, self-injurious behavior, and attractiveness—with staff expectations of and frustration with clients. Forty staff members who worked with severely and profoundly retarded individuals served as participants. Staff members rated each client with whom they worked on the extent to which the client could behave better and learn faster as well as the level of frustration experienced in working with the client. A client's functioning level was related to staff perceptions such that the higher the functioning level, the more the client was seen as having the potential to behave better or learn faster than (s)he was presently demonstrating. Staff frustration was related to client aggression indicating that as aggression increased so did staff frustration in working with that client. Implications of the results are discussed.  相似文献   
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A suite of programs is described for simulating the Rescorla-Wagner (1972) model of associative learning, the Solomon and Corbit (1974) opponent-process theory, and Schull’s (1979) extension of the latter. The programs are written for the Commodore 64 computer.  相似文献   
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