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181.
This study investigates the expression of attitudes by individuals within the context of groups. A link is made between two theoretical areas: that of intergroup relations and that of the effects of group interaction on the expression of opinions. It is argued that individuals in groups adopt more polarized attitudes to achieve a more positively distinct group identity, and to afford themselves identification with that group. Subjects individually expressed their opinion on an issue, while the salience of group membership was varied by evoking the identity of an alternative group which held opposed opinions on the issue. When their own group identity was more salient, subjects tended to express their opinions in a more polarized manner, and in a manner more in keeping with the presumed view of their group. Also, they attributed to the other group attitudes that were more polarized and more in keeping with their presumed view of the issue.  相似文献   
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183.
A coaching strategy to decrease errors in swimming strokes with swimmers who had not improved under "standard" coaching procedures was investigated using a multiple baseline design across subjects and swimming strokes. The procedure resulted in a large decrease in errors on swimming strokes during sessions in a training pool. Stimulus generalization of improved performance to normal practice conditions in the regular pool was observed with all but one swimmer. This improvement was maintained during two maintenance phases lasting approximately 2 weeks, as well as under standard coaching conditions during at least a 2-week follow-up. For two swimmers, error rates on one of the strokes showed a gradual increase between the third and fifth week of follow-up, but brief remedial prompting sessions immediately corrected their performance. Some beneficial response generalization to other components of the stroke being trained was observed, but no improvements were found on untrained strokes. The error correction package did not disrupt practice, require excessive amounts of the coach's time, or necessitate the use of cumbersome apparatus. In addition, the coach and the swimmers considered the procedures to be effective, and expressed their willingness to participate in them again in the future.  相似文献   
184.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
185.
The effects of task demands on the visual comparison of facial patterns and of comparable nonfacial patterns were explored in two studies. The studies yielded two primary findings. First, faces, despite their holistic properties, are not rotated faster than comparable non-face-like patterns, although subjects’ judgments of them were uniformly more rapid than judgments for nonfaces. Second, the nature of the same-different judgment task required of subjects had a large effect on the pattern of results obtained: When stimuli were compared to their mirror images, results indicative of mental “rotation” were obtained. When stimuli were compared on the basis of similarity of individual features, the pattern of results was very different. This one manipulation produced effects that exceeded those of all of the other manipulations, including that of rotation.  相似文献   
186.
Self-perceived competence in three roles (parent, social participant, self-supporter) was examined in relation to life satisfaction in a sample of 47 divorced, employed, single parent, middle-income women. Parenting was found to be the role of greatest perceived competence, and self-supporter the role of lowest perceived competence. Competence as a self-supporter was the strongest predictor of life satisfaction. Life satisfaction did not differ significantly between groups defined by length of time as single parents. For women separated less than 3 years, the social participant was the role of least perceived competence and the best predictor of life satisfaction. For those separated more than 3 years, the three roles were nearly equal in perceived competence, but competence as self-supporter was the best predictor of life satisfaction.  相似文献   
187.
The effects of emotionality of study tasks on face recognition were examined. Subjects made either personality decisions or self-comparisons about the people shown in a series of photographs. The personality traits judged during the encoding tasks had been selected to be either arousing or relatively nonarousing. Face recognition performance was best after an emotional nonself study task, on both immediate and delayed tests. In a companion study examining these manipulations in verbal memory, self-reference study tasks produced the best word recognition, with no difference due to the emotionality of nonself tasks. These results suggest emotionality and self-awareness have different effects on facial and verbal memory. A final study indicated that the effect of emotionality disappeared if it was added to self-reference. As regards self-reference differences in face and verbal memory, this series of experiments seems to rule out an emotionality confounding. It was concluded that self-images are less effective mnemonic aids than the propositional self-concept.  相似文献   
188.
189.
An experiment is described in which the effects of Psychoticism and Extraversion on classical eyelid conditioning were examined using a balanced design involving two levels of paraorbital shock intensity and two levels of response threshold. Questionnaire measures of Anxiety and Impulsivity were also analysed together with subjective ratings of the UCS. Results were broadly consistent with Eysenck's personality theory in that subjects scoring high on Psychoticism demonstrated lower levels of conditioning.  相似文献   
190.
Group learned helplessness is demonstrated in Experiment I. Groups of 2 tried to turn off noise by their joint action. In the solvable group (S), noise offset was contingent on their sequence of button pushing. In the yoked, unsolvable group (U), noise offset was independent of all sequences of button pushes they produced. In a practice group (O). subjects practiced coordinated sequences of button pushes with their partners, but heard no noise. Later, all 3 groups were tested in pairs in a shuttlebox which required coordinated joint responding to turn off noise. The unsolvable group escaped more poorly than the other 2 groups, paralleling helplessness effects with individuals. Experiment 2 and 3 found no transfer from individual helplessness training to group testing and no transfer from group helplessness training to individual testing. We suggest that the same mechanism, the expectation of response ineffectiveness, may mediate both individual and group learned helplessness.  相似文献   
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