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781.
This study is concerned with the manner in which Western mathematics is assimilated by children raised in traditional African cultures. It was predicted that after an initial period of difficulty in learning school arithmetic, African children (Baoulé and Dioula from the Ivory Coast) acquire basic concepts, develop invented strategies, and make errors similar to those of American children. Further, it was predicted that Dioula children, since they are members of a commercial culture, perform at a somewhat higher level than the Baoulé, members of a farming culture which does not seem to stress computational activity. To investigate these hypotheses, American, Baoulé, and Dioula children at two age levels were given a variety of arithmetic problems involving basic skills (e.g., reading numbers), number knowledge (e.g., place value), and calculational abilities (e.g., written computation). The results showed that, in general, older African and American children (fifth- and sixth-graders) were quite similar in all respects. The only large and significant differences occurred in the case of younger children (second- and third-graders). At this level American children generally performed at a higher level than Africans, as predicted, and Dioula occasionally at a higher level than Baoulé, also as predicted. At the same time, qualitative aspects of African and American children's performance were similar: for example, both groups made the same types and proportions of errors in written calculations. The results generally support the hypotheses and can be explained in terms of both educational and cognitive factors.  相似文献   
782.
Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.  相似文献   
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787.
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   
788.
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   
789.
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   
790.
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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