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51.
A simple dc shock-generating device is described. The principle of operation relies upon the mutual inductance effect between the primary and secondary coils of a transformer.  相似文献   
52.
Normative data are presented for Southern black children on two objective personality inventories for children: the Missouri Children's Picture Series (MCPS), a child picture-sorting task, and the Missouri Children's Behavior Checklist (MBCL), a parent rating scale. The MCPS was administered to 615 black children attending public schools in a low socioeconomic area of the southeast United States. Parents returned the MBCL on 437 of the children. Means and standard deviations on eight MCPS personality scales and six MCBL behavior rating scales are presented for black males and females at ages 5 through 16, and effects of age, sex, and various scale intercorrelations are discussed. Results suggest systematic age and sex differences on the various scales for black children that are quite atypical when compared with the MCPS in other samples. Various empirical questions regarding the validity of these instruments when used with Southern black children are raised.  相似文献   
53.
This paper describes a seven-stage model of post-adolescent reasoning styles, the most advanced of which is called “Reflective Judgment.” The model outlines a sequence of increasingly complex methods of justification of beliefs. This model demonstrates how people's conceptions of the nature of knowledge, the nature of reality, and their concepts of justification change over age/educational levels. Sixty subjects from three age/educational levels (high school, college, and graduate school) were administered the Reflective Judgment Interview. In addition, subjects were tested on four other factors hypothesized to affect reflective judgment scores. Two were competing theoretical constructs: verbal ability (using Terman's Concept Mastery Test) and Piagetian formal operations (chemicals and pendulum tasks); and two were potentially confounding factors: socio-economic status (using Hollingshead's two-factor index) and verbal fluency (number of words spoken during the interview). Highly significant differences (p < .001) were found on reflective judgment level between the three age/educational groups, and could not be statistically accounted for by scores earned on measures of the other four factors. Whereas verbal ability was found to be closely related to reflective judgment level, the differences between groups on reflective judgment could not be solely attributed to this factor.  相似文献   
54.
Twelve hundred and fifty college students starting introductory courses in thirteen academic disciplines were asked to predict their grade in the course. Results showed that overall, males predicted higher grades for themselves than did females (p <.001). This held true for entering freshmen as well as for those with previous college experience. The phenomena was noted in 26 of 37 classes tested, including 7 of 9 in the natural sciences, 11 of 13 in the social sciences, but only 8 of 15 in the humanities. Sex of the instructor was irrelevant, raising the question of whether female instructors as role models have the positive effect upon women students that has been claimed. The differences found were slight, but persistent. Both sexes predicted very high grades. The data suggest that sex differences in prediction were not based on a female sense of incompetence, but upon a greater willingness among males to make highly positive predictions.  相似文献   
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