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991.
The experiments in which the strengths of pattern and of fusion differing in kind from brightness were used as measures indicated that the visual system could distinguish between illuminance and reflectance. From this result and an observation of gray papers by a microscope, it is assumed that luminance has two aspects, one refers to the macroscopic density of photons and another to the proportion of the reflected microscopic areas to the absorbed microscopic areas so that brightness constancy occurs in relation to each of the patterns of the various sizes from a macroscopic pattern visible to the naked eye to a microscopic pattern not visible. It is also mentioned that the strength of fusion is rare but promising as a measure for analyzing brightness. 相似文献
992.
835 community college students were surveyed to establish the prevalence of head injury or illness. Results are compared to prevalence rates among 4-year college students. 相似文献
993.
994.
T S Mwamwenda 《Perceptual and motor skills》1991,73(1):191-194
To examine sex differences in self-concept among black African adolescents in Umtata, South Africa, 97 boys and girls whose mean ages were 18.0 and 17.7 yr., respectively, were drawn from St. John's College students who were in their final year of high school and were preparing for their final year and national matriculation examinations. On the Canadian Self-esteem Inventory mean scores obtained by girls and boys were not significantly different. 相似文献
995.
Biobehavioral factors in sudden cardiac death 总被引:2,自引:0,他引:2
The authors examine the recent literature on psychological factors and sudden cardiac death and explore the mediating psychophysiological processes by which these variables may be associated. Direct evidence that psychosocial stressors and their correlates may be causally linked with sudden cardiac death in humans is not conclusive, but there is abundant convergent evidence that several physiological precursors of sudden death may be promoted by psychological challenge, especially in persons with coronary heart disease. The authors call for increased attention to the acute effects of psychological events on cardiovascular health. 相似文献
996.
T A Roberts 《Psychological bulletin》1991,109(2):297-308
This article reviews evidence for a gender difference in responsiveness to others' evaluations in achievement situations. Studies show that women's self-evaluations are more responsive to the valence of the evaluative feedback they receive than are men's. A number of possible explanations for this effect are then discussed, with the best evidence pointing to men's and women's differing construals of the informational value of others' evaluations in such situations. Research on the behavioral consequences of women's lower status as well as on children's experiences with evaluative feedback provides potential explanations for this effect. A more proximal explanation, however, lies in men's and women's different approaches to evaluative achievement situations. Men may be particularly likely to respond to the competitive nature of evaluative achievement and hence to adopt a self-confident approach that leads them to deny the informational value of others' evaluations. Women may be particularly likely to approach such situations as opportunities to gain information about their abilities. 相似文献
997.
The Psychological Record - Compliance with instructions to respond on response-independent schedules was studied to see if schedule insensitivity is determined by reinforcement of inappropriate... 相似文献
998.
In recent years, many organizations have attempted to pursue continuous improvement through team-based employee involvement programs (EIPs). As a result, increased practical emphasis has been placed on how to design and administer EIPs, though empirical work has been slow to emerge. In the present research, a pilot study of 68 EIP administrators was used to identify those design and administrative variables thought to be associated with EIP effectiveness. Data were then collected from 72 EIP teams in two organizations and associated with participant and supervisory assessments of EIP effectiveness. Results suggest that the significant predictors of team effectiveness were the degree of openness of a team's information access structure, the degree of heterogeneity in the job functions performed by team members, and the team's size. Implications for EIP research and practice are discussed. 相似文献
999.
The Kaufman Test of Educational Achievement--Brief Form and the Wide Range Achievement Test--Revised Level 2 were administered in counterbalanced order to 50 male incarcerated juvenile delinquents. The analyses showed the similar subtests on the two tests, i.e., Kaufman Reading test and WRAT-R Reading, were highly correlated. The mean standard scores of th e similar subtests were not significantly different from each other. These results contrast with the significantly lower WRAT-R scores found when scores on the WRAT-R Level 1 are compared with those on the Kaufman test. 相似文献
1000.
A model of category effects on reports from memory is presented. The model holds that stimuli are represented at 2 levels of detail: a fine-grain value and a category. When memory is inexact but people must report an exact value, they use estimation processes that combine the remembered stimulus value with category information. The proposed estimation processes include truncation at category boundaries and weighting with a central (prototypic) category value. These processes introduce bias in reporting even when memory is unbiased, but nevertheless may improve overall accuracy (by decreasing the variability of reports). Four experiments are presented in which people report the location of a dot in a circle. Subjects spontaneously impose horizontal and vertical boundaries that divide the circle into quadrants. They misplace dots toward a central (prototypic) location in each quadrant, as predicted by the model. The proposed model has broad implications; notably, it has the potential to explain biases of the sort described in psychophysics (contraction bias and the bias captured by Weber's law) as well as symmetries in similarity judgments, without positing distorted representations of physical scales. 相似文献