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951.
The present study compared two hypotheses about children's solutions to Piaget and Inhelder's (1975) two-set alternative choice probability problems. The first was that children follow rules that specify a temporally ordered sequence of tests and decisions (Siegler, 1981). One prediction of rules is that children who know strategies that combine variables within sets (e.g., ratio or subtraction strategies) will only use them on problems that require such strategies (conflict problems), whereas lower level (nonconflict) problems will be solved by directly comparing the values of variables between sets. The second hypothesis was that once children develop knowledge of within-set solutions to probability problems, they apply them to both conflict and nonconflict problems. The results supported the latter hypothesis. The majority of children who solved conflict problems using within-set strategies explained at least one nonconflict problem by referring to within-set combinations. Results were discussed in terms of their implications for cognitive development and for instruction. 相似文献
952.
David E. Sandberg Anke A. Ehrhardt Claude A. Mellins Susan E. Ince Heino F. L. Meyer-Bahlburg 《Sex roles》1987,16(11-12):649-668
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
953.
SEX DIFFERENCES IN MORAL JUDGMENTS? A TEST OF GILLIGAN'S THEORY 总被引:1,自引:0,他引:1
954.
3-6岁幼儿在分类实验中概括能力的发展 总被引:5,自引:0,他引:5
本研究通过设计不同性质的分类实验,探讨3-6岁幼儿抽象概括能力的发展。我们根据年龄将幼儿分为四个组,每组80人,共320人。通过实验获得以下几点。①幼儿在各种不同性质的分类实验中可表现为四级不同的水平,如从根据表面的个别特征进行分类发展到根据内部的本质特征进行分类,从一维角度的分类发展到从两维角度来分类等。⑦达到各个水平的年龄不是截然划分的,而是互相交织的,随着年龄的增加,低级水平的人数不断减少,高级水平的人数不断增加。所以年龄阶段之间既有质的变化,又有量的变化。③对于不同性质的分类材料,各年龄所达到的概括水平也不同,分类材料的难度越大,概括水平越低。④儿童概括水平的高低受教育条件的影响。 相似文献
955.
Sixteen student volunteers were administered a placebo and 50 mg. of chlorpromazine in tablet form, on separate occasions,
two hours before testing. The three tests measured dichotic listening performance, lateral eye movements while answering questions
about spatial location and verbal meaning, and lateralized facial expression while relating pleasant and unpleasant life incidents.
Results showed that chlorpromazine increased the number of trials showing an ear advantage in dichotic listening. Chlorpromazine
reduced lateral and increased vertical eye movements in response to the questions about spatial location and verbal meaning.
Under the placebo both negative and positive emotions were expressed more in the left face. Although chlorpromazine did not
affect this lateralization of negative emotions, the expression of positive emotions occurred equally often on the two sides
of the face under chlorpromazine. Results may be related to an effect of chlorpromazine on the asymmetrical dopamine pathways
of the brain. It is suggested that the findings may be related to a left hemisphere deficit in schizophrenia. 相似文献
956.
Normative data are presented for the probability of successfully completing 192 single-solution word fragments. Normative data on the familiarity of college students with the solution words are also given, along with estimates of word frequency from existing norms. Regression analyses were performed in order to predict fragment completion difficulty from familiarity, frequency, and several structural characteristics of the fragments. Familiarity, whether or not first and/or last letters appeared in the fragment, and the ratio of letters to missing letters in the fragment were included in the regression equation as significant predictors of difficulty for this fragment set. 相似文献
957.
Howard L. Kaplan 《Behavior research methods》1987,19(2):210-214
The Scheduled Measurement System (SMS) is a collection of related programs for administering performance and rating tasks to human subjects. It was designed to provide a common task scheduling and data management environment for a diversity of measures. SMS has greatly reduced the effort required to analyze and archive data after experiments, but it has been less successful in reducing some of the effort required to implement experiments. While programming is not difficult, documentation and user training remain the most primitive parts of the system. 相似文献
958.
959.
Thomas P. Pallmeyer Edward B. Blanchard Lawrence C. Kolb 《Behaviour research and therapy》1986,24(6):645-652
The psychophysiological responses of heart rate (HR), systolic and diastolic blood pressure, skin conductance level and forehead electromyogram were compared during: rest, mental arithmetic and combat sounds of gradually increasing intensity for five groups of Ss: Vietnam veterans with post-traumatic stress disorder (PTSD); Vietnam veterans without PTSD but with comparable levels of combat experience; Vietnam veterans with other psychiatric disorders; Vietnam-era veterans; and nonveteran phobics. HR response to low-intensity combat sounds provided good discrimination between veterans with PTSD and the other groups and seems to resemble a conditioned emotional response. 相似文献
960.
The prevalence of DSM-III conduct and adjustment disorders in two adolescent psychiatric facilities, both located near large U.S. cities, was investigated. Overall, 31.6% of the adolescent inpatients were conduct disordered while 12.5% were adjustment disordered. The conduct disorders were primarily "aggressive" subtypes suggesting that this characteristic may influence hospitalization and diagnostic decisions. Such data on prevalence assists future treatment planning, allowing anticipation of case loads. 相似文献