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131.
Historically, women and minority group members have been underrepresented in the professions and in better paying, high-status jobs. Even when they have been admitted to such positions, these underrepresented persons often have been the only member of their social category: a token. Previous field and laboratory research has shown that "tokens" attract disproportionate attention and are either evaluated unfairly or evaluated on the basis of their normal reactions to differential treatment by majority group members. We tested the possibilities of whether tokens might suffer more cognitive deficits than would nontokens, and whether they do so even when they are treated no differently. College students were led to believe that they were sharing their views on everyday topics with three other students (actually videotaped confederates), who were either all of the student's own sex or all of the opposite sex. In a later memory test, token participants remembered fewer of the opinions that they and the three other students had expressed than did nontokens. Observers, in contrast, remembered more of what token subjects said than what the three other students said. Theoretical and public policy implications are discussed.  相似文献   
132.
A common criticism of iterative least squares estimates of communality is that method of initial estimation may influence stabilized values. As little systematic research on this topic has been performed, the criticism appears to be based on cumulated experience with empirical data sets. In the present paper, two studies are reported in which four types of initial estimate (unities, squared multiple correlations, highestr, and zeroes) and four levels of convergence criterion were employed using four widely available computer packages (BMDP, SAS, SPSS, and SOUPAC). The results suggest that initial estimates have no effect on stabilized communality estimates when a stringent criterion for convergence is used, whereas initial estimates appear to affect stabilized values employing rather gross convergence criteria. There were no differences among the four computer packages for matrices without Heywood cases.  相似文献   
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Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.  相似文献   
136.
The author diagnoses 350 carefully selected schizophrenic subjects, their parents and their siblings during parallel studies using three different clinical classification systems and analyzes the results by multiple threshold analysis and the multifactorial inheritance model. The results suggest that, of the three classifications the author studied, Leonhard's and Sneshnewski's system yield relatively homogeneous subgroups; this indicates the future significance of these nosological systems for the planning of biopsychiatric research.  相似文献   
137.
40 women were taught to use self-statements to cope with pain caused by ice water. The trainer used four different strategies for reassigning a homework task of using self-statements to cope with pain produced by immersing one hand in ice water. The strategies were equally effective in eliciting compliance with the homework assignment.  相似文献   
138.
On the basis of the hypothesis of misapplied constancy scaling, the perception of an abstract horizontal-vertical illusion figure embedded in photographs of natural scenes with depth cues is investigated. The effect is compared with that of a figure on photographs containing no depth information and with a figure on a neutral surface. It is shown that the magnitude of the illusion in the perspective scenes is greater than in the other two conditions. The results are considered compatible with a constancy theory of the illusion. Finally, the evidence for misapplied constancy scaling in the horizontal-vertical illusion in relation to a retinal theory is discussed.  相似文献   
139.
Improvement in auditory-successive selective attention was noted across the age range of 9 through 16 yr. In contrast to comparable paradigms with visual-simultaneous materials, 30 learning disabled and 30 normal boys did not differ. Results of research on selective attention may be affected by task materials and encoding requirements.  相似文献   
140.
Distributions of reinforcers between two components of multiple variable-interval schedules were varied over a number of conditions. Sensitivity to reinforcement, measured by the exponent of the power function relating ratios of responses in the two components to ratios of reinforcers obtained in the components, did not differ between conditions with 15-s or 60-s component durations. The failure to demonstrate the “short-component effect,” where sensitivity is high for short components, was consistent with reanalysis of previous data. With 60-s components, sensitivity to reinforcement decreased systematically with time since component alternation, and was higher in the first 15-s subinterval of the 60-s component than for the component whose total duration was 15 s. Varying component duration and sampling behavior at different times since component transition may not be equivalent ways of examining the effects of average temporal distance between components.  相似文献   
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