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31.
This study uses data from adolescents matched with data from their friends to examine whether reference group effects on adolescent sexuality should be thought of as operating through the sharing of norms or the modeling of behavior. We observe that perception of attitudes has such a trivial reality component and such a strong autistic component that it cannot serve as a mechanism of peer influence. Perception of sexual behavior has a reality component which is as large as its autistic component, and large enough to serve as a route of influence. We reach two conclusions: (1) Reference group effects on adolescent sexual behavior probably work through behavior modeling rather than through normative influence. (2) Studies which infer peer influence on sexual behavior using only perception of peers will arrive at erroneous conclusions.  相似文献   
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A method of hardware reaction timing with millisecond accuracy, using one of the Amiga’s CIA 8520 chips, is described. The registers of this chip can be set to enable cascaded timing that functions independently of the CPU and, thereby, avoids the problems of software timing in a multitasking environment. In addition, the interfacing of a pair of reaction-time keys to one of the Amiga’s game controller connectors and a program for polling this port for keypresses are described.  相似文献   
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The present study examined the hypothesis that violation and role-playing instructions are necessary conditions for facilitation on Wason’s selection task and that facilitation due to memory cueing via thematic content is secondary. The results of a factorial experiment employing these factors did not support the hypothesis. Memory cueing was indicated as the primary factor, but violation instructions did increase the amount of facilitation observed. This interactive effect and the nature of facilitation by memory cueing are briefly discussed.  相似文献   
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The present study explored individual differences in performance of a geometric analogies task. Whereas past studies employed true/false or two-alternative items, the present research included four-alternative items and studied eye movements and confidence judgements for each item performance as well as latency and error. Item difficulty proved to be a function of an interaction between the number of response alternatives and the number of elements in items, especially for subjects lower in fluid-analytic reasoning ability. Results were interpreted using two hypothesized performance strategies: constructive matching and response elimination. The less efficient of these, response elimination, seemed to be used more by lower ability subjects on more difficult items. While two previous theories resemble one or the other of these strategies, neither alone seems to capture the complexity of adaptive problem solving. It appears that a comprehensive theory should incorporate strategy shifting as a function of item difficulty and subject ability.Componential models, based in part on past research, revealed that a justification component was activated and deactivated depending upon the nature of the analogy being solved. In addition, two new components, spatial inference and spatial application, were identified as important on some items, suggesting that different geometric analogy items invoke different cognitive processing components. Thus, a comprehensive theory should also describe component activation and deactivation.  相似文献   
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Although one-to-one correspondence can be seen as a component of successful counting, number conservation, and relative number judgments, there is evidence of considerable discrepancies between children's competencies in these different tasks. Concerning relative number judgments there are strikingly different claims concerning the ability of young children to make one-to-one correspondence-based judgments. In part these discrepancies reflect differences in criteria. Four experiments are reported in which 5-year-olds' relative number judgments of small and large number displays with and without perceptual aids were studied. Children were found to respond to local rather than global density differences and to benefit from the provision of perceptual aids on both small and large number displays with one exception, namely, large number displays where the longer row is less numerous.  相似文献   
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