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Relation algebras from cylindric and polyadic algebras 总被引:1,自引:0,他引:1
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Paul M. Kohn Colleen O'Brien Donna I. Pickering 《Personality and individual differences》1997,22(6):895-899
Adaptiveness constitutes coping consistently with Stressors so to reduce distress or, at worst, not aggravate it. Accordingly, it should moderate the adverse impact of hassles. Undergraduate volunteers (N = 200) responded to measures of hassles, adaptiveness, and the criteria of subjective distress, psychiatric symptomatology and minor physical ailments. In all three regression analyses, hassles made a substantial positive contribution and adaptiveness a small negative contribution to adverse outcome. The interaction between hassles and adaptiveness was non-significant in all three cases. Alternative interpretations were identified to guide further research. 相似文献
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Patrick R. Laughlin Vicki J. Magley Ellen I. Shupe 《Organizational behavior and human decision processes》1997,69(3):265-275
In a rule induction problem positive hypothesis tests select evidence that the tester expects to be an example of the correct rule if the hypothesis is correct, whereas negative hypothesis tests select evidence that the tester expects to be a nonexample if the hypothesis is correct. Previous research indicates the general effectiveness of a positive test strategy for individuals, but there has been very little research with cooperative groups. We extend the analysis of Klayman and Ha (Psychological Review, 1987) of ambiguous verification or conclusive falsification of five possible types of hypotheses by positive and negative tests by emphasizing the importance of further examples following hypothesis tests. In two experiments four-person cooperative groups solved rule induction problems by proposing a hypothesis and selecting evidence to test the hypothesis on each of four arrays on each trial. In different conditions the groups were instructed to use different combinations of positive and negative tests on the four arrays. Positive tests were more likely to lead to further examples than negative tests, and the proportion of correct hypotheses corresponded to the proportion of positive tests, in both experiments. We suggest that positive tests are more effective than negative hypothesis tests in generating further evidence, and thus in inducing the correct rule, in experimental rule induction tasks with a criterion of certainty imposed by the researcher. 相似文献
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Abstract— The apparent brightness of a surface is profoundly influenced by the brightness of an adjacent surface., but these contrast effects are reduced when the surface are perceived as separate three-dimensional entities. Previous work has suggested that high-level perceptual and cognitive processes involved in scence segmentation may be responsible for modifying a surface's appearance. We demonstrate large reductions in contrast effects when the sues available for segmentations are restricted to those that isolate separate groups of early cortical neurons in the visual system. Our data contradict standard contract-signaling models of brightness perception and imply that mechanisms of figure-ground segmentation are already available at low levels of visual processing. 相似文献
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Abstract— Generating a use far a visual word in comparison with reading the word aloud activates frontal attention areas first (170 MS), a left lateral frontal area next (250 ms), and then a left temporoparietal (Wernicke's) area (650 ms). A brief period of practice reduces these activations. If subjects are asked to respond to a word from the same practiced list by giving a novel use, the original activations reappear and are joined by activity similar in location and time to Wernicke's activation but in the right hemisphere. These findings demonstrate the time course of activations of neuroanatomical areas in word processing and indicate a role for the right hemisphere when semantic processing is more difficult, such as in generating a less frequent association in the presence of a highly practiced one. 相似文献