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961.
This study measured racial attitudes of 201 students toward American Indians in a variety of social-interpersonal and educational situations. Student's racial attitudes were generally positive except in a situation involving an American Indian student receiving free health care. Results are discussed in the context of the current sociopolitical climate.  相似文献   
962.
Abstract— Ancient and medieval scholars considered tones related by simple (small-integer) ratios to be naturally pleasing, but contemporary scholars attribute the special perceptual status of such sounds to exposure. We investigated the possibility of processing predispositions for some tone combinations by evaluating infants' ability to detect subtle changes to patterns of simultaneous and sequential tones Infants detected such changes to pairs of pure tones (intervals) only when the tones were related by simple frequency ratios. This was the case for 9-month-old infants tested with harmonic (simultaneous) intervals and for 6-tnonth-old infants tested with melodic (sequential) intervals. These results are consistent with a biological basis for the prevalence of particular intervals historically and cross-culturally.  相似文献   
963.
Sandra Acker 《Sex roles》1977,3(3):285-299
This paper compares men and women graduate students at one university and identifies conditions under which women students equal or surpass men in ambition. Men and women were broadly similar in background characteristics, though different in current family status. They studied different subjects, aimed for different degrees, and were concentrated in different years in the university. If women were to equal the most highly ambitious men on ambition to publish and engage in related behaviors, they had to aspire to a doctorate, survive past the second year of study, and have nontraditional attitudes toward women's role. The results are discussed in terms of differential student careers and barriers to the development of ambition in student women.The research upon which this paper is based was carried out with the assistance of a Lena Lake Forrest Fellowship from the Business and Professional Women's Foundation, Washington, D.C.The author wishes to thank G. L. Millerson and C. T. Husbands for comments on the draft, and Beryl Collins and Bryn Saunders for help with the typing.  相似文献   
964.
Depth perception in the Mongolian gerbil was investigated as a function of age and environment. Thirty-two gerbils were raised in either a cliff or flat environment, and half the gerbils in each condition were tested on the visual cliff from 21 to 57 days of age. All gerbils were tested at 60–61 days on a standard visual cliff, a barrier cliff which prevented movement along the centerboard, and a jumping platform. While the gerbils did not display a preference for the shallow side when tested at 21 days, those living in a cliff environment showed rapid acquisition of such a preference, whereas those living in a flat environment did not. By 60–61 days, however, all gerbils demonstrated a strong preference for the shallow side on both versions of the visual cliff, regardless of environment or pretesting experience.  相似文献   
965.
Six subjects, comprising one class at a school for the deaf, were given reinforcement consisting of time free from school work for remaining seated in the classroom. As a result, the frequency of leaving their chairs was sharply reduced. A second procedure presented free-time not contingent on remaining seated. Little change was seen in the already lowered response rate. An extension of the time required to be seated with corresponding reduction in the number of daily free-time periods did not reduce the effectiveness of the procedure. A one-day observation after six weeks indicated that the procedure was still effective. A one-day contingency reversal, requiring subjects to leave their chairs at least once during each seated period in order to receive free-time, substantially raised the frequency of out-of-seat responses.  相似文献   
966.
967.
968.
Women's lower achievement level in the professions is explained by the Multiple Role Negotiation perspective as resulting from the difficulty in balancing the “active” or demanding roles of wife/mother and a high level professional role. The Value Difference perspective, on the other hand, explains this differential achievement as resulting from differences in degree to which women value professional roles and their familial role, with perceptions of “demand” serving only as “excuses” to mask values. To explore the assumptions of each position three research questions are posed and 33 first-year students in a professional program are surveyed. The findings reveal that neither males nor females perceive the female familial role as the “more active” one; females, however do anticipate less career advancement, value the higher level role less, and also perceive it as a more demanding role than the lower level role.  相似文献   
969.
Components of a computer solution for fraction problems in arithmetic have an analog in a new approach to educational task analysis. The components may be called goal-setting or planning elements, in contrast to the goal-satisfying or behavioral steps emphasized in much contemporary task analysis. A hypothetical tutorial dialogue in which a student is asked to tell a tutor what step to perform next is presented as an example of the emphasis of the planning side of computation. Explicit identification of goal-setting elements of a task is illustrated by analysis of the task of converting a pair of fractions to a new pair with a common denominator. The decomposition thus produces is simulated with two computer programs: (1) a LISP program using a set of production rules consisting of conditions to be met and subsequent actions to be taken and (2) a PROLOG program stating goals and solving goals explicitly.  相似文献   
970.
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