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941.
Recent literature has suggested there is a causal link between malnutrition and impaired cognitive development. From a selective review of this literature it is concluded that owing to methodological imperfections in many of these studies the presence or absence of such a link cannot be established, even if randomized experiments were to be carried out. It is argued that compensatory experiments, even though they are not as logically compelling as experiments where proper nutrition is withheld, are ethically justifiable and more useful strategically since they may suggest ways of improving the cognitive development of currently affected children, especially if a variety of compensatory treatments is implemented. A reanalysis of such an experiment was conducted to determine whether the nutritional or educational component of the treatment was responsible for the observed gains in cognitive development. The reanalysis indicated that after four years of treatment there was no association between cognitive and nutritional status. The results were discussed in relation to previous research. Some of the social implications of the results were also discussed.  相似文献   
942.
The “factor” analyses published by Schultz, Kaye, and Hoyer (1980) confused component and factor analysis and led in this case as in many others to unwarranted conclusions. They used component analysis to develop factor models that were subjected to restricted (confirmatory) maximum likelihood analysis, but the final models for which good fits with the observed correlations were obtained were not common factor models. They were, however, discussed as such and conclusions drawn accordingly. When their correlation matrices are analyzed by the principal factors method, two factors are sufficient to account for the intercorrelations. These two factors generally support the a priori expectation of a difference between intelligence tasks and spontaneous flexibility tasks. They are also quite similar in younger and older subjects, when similarity is judged in terms of factor pattern. Factor loadings for the younger subjects, however, are much smaller than expectations based on the respective ranges of talent in the two groups of subjects or on past experience with similar tests in undergraduate student populations.  相似文献   
943.
Medication effects in the classroom: Three naturalistic indicators   总被引:2,自引:0,他引:2  
Hyperactive and comparison boys participated in 5-week summer enrichment programs that included classroom activities and structured assessments of peer interaction patterns. During the 3rd and 4th weeks of these programs, a double-blind, methylphenidate-placebo crossover design was implemented within the hyperactive group. Three heterogeneous indicators of everyday behaviors were obtained: number of negative incidents noted by staff, quality of handwriting, and number of times the teacher called the boys' names aloud in the classroom. Medication effects emerged for each of these indicators. When hyperactive boys were taking placebos, they were involved in more negative incidents, their handwriting was poorer, and their names were called more frequently than when the boys were taking methylphenidate. Interrelationships among the measures suggest moderate cross-situational generality of medication responsiveness. Discussion focused on the bandwidth of medication effects and the need to examine the social ramifications of child treatments.This research was supported in part by NIMH grant 29475 and NIDA grant 01070. We gratefully acknowledge the participation of the data coders and the many summer school staff. Special thanks go to Mike Berlin, Barry E. Collins, and Sharon Dotemoto. Methylphenidate and placebo were supplied by Ciba-Geigy, Summit, New Jersey.  相似文献   
944.
945.
Three experiments examined the influence of videotaped classroom events on the academic performance and study behavior of reading-disabled and normally reading children in grades 1 through 6. In experiments 1 and 2a an experimenter-controlled presentation of these distractors resulted in performance decrements, the magnitude of which was greater for higher difficulty tasks. The distractor effects were similar for the two groups in this condition. However, when the children themselves were allowed to control their degree of exposure to the same distractors in experiment 2b, the reading-disabled children were less likely to act to escape the distraction. Results are discussed in terms of children's metacognitive awareness of distraction, and implications for the classroom are considered.  相似文献   
946.
In an attempt to clarify the relation between parental variables, sexual preference, and sex-role attitudes, three groups of women were studied: lesbian feminists, heterosexual feminists, and heterosexual traditional women. The women were asked about their perceptions of their parents when they were in high school. The groups differed more from each other with respect to their perceptions of their fathers than their mothers. The perceived attitudes of the father were much more important in differentiating lesbian feminists from heterosexuals than in differentiating heterosexual feminists from heterosexual traditionals. Both the heterosexual groups (feminist and traditionals) reported having a more affectionate and involved father who also encouraged them more in the expression of anger than the lesbian feminists reported. The results suggest women's father relationships must not be obscured in research and support Johnson's hypothesis that the father relationship is more central than the mother relationship in sex typing and especially in the specifically sexual aspects of sex typing.  相似文献   
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948.
949.
In an investigation of the effects of stem structure and direction set on sentence completion responses, 160 undergraduate males were randomly assigned to one of four conditions: Rotter ISB with "feelings" instructions, Rotter ISB with "speed" instructions, Sacks SCT with "feelings" instructions, Sacks SCT with "speed" instructions. Eight clinical judges derived hypotheses from the completed protocols; two judges evaluated each protocol. Interjudge reliability was measured by Pearson product-moment correlations and percents of agreement. There was a significant effect for amount of stem structure; the structured Sacks SCT stems yielded more clinical hypotheses. Structured stems also elicited significantly more feeling words. No significant effect was found for instructional set, nor was there a significant relationship between stem structure or instruction set and the numbers of words in completions.  相似文献   
950.
Most dimensional analyses of traditional Rorschach scoring categories have either failed to control for differences in total R or have done so by introducing a nonstandard mode of administration. Consequently, the results of such studies may be either distorted or of questionable relevance to more typical situations. The present analyses, which compared both group and individual forms of the Rorschach administered to large samples (over 500 each) of male medical students, controlled for differences in total R by using residualized scores from which the linear effects of R had been partialled. The factor-analytic results are expressed in terms of seven easily interpretable factors (including total R), five of which are similar across forms, and simple formulas for deriving norm-referenced factor scores from the data of individual test administrations are provided.  相似文献   
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