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441.
Edmund R. Peay 《Psychometrika》1975,40(4):573-574
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G. C. Preston A. Dickinson N. J. Mackintosh 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1986,38(2):217-237
Three experiments used a discriminated operant procedure to study conditional discrimination learning in rats. The first experiment showed that rats were capable of learning a biconditional discrimination in which two contexts served as conditional cues signalling the reinforcement contingencies associated with two discriminative stimuli. The discrimination was learned equally well when one discriminative stimulus signalled food, the other its absence, and when one stimulus signalled food, the other extinction plus mild footshock.
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
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This study examines the effects of certain communication variables (member integration, boundary communication, environmental uncertainty, and system autonomy) on organizational effectiveness. While often discussed in the literature, these variables have not been precisely defined. As a result, a multiple indicator model using maximum likelihood estimates for each variable was created. Interviews with managers from 82 different organizations from a variety of industries are used to test the model. The results suggest that member integration and environmental uncertainty, when the latter is mediated by boundary communication, provide an excellent predictor of organizational effectiveness (R= .64). The results are discussed in light of the proposed theory along with implications for future research using intertypical sampling methods and LISREL analysis. 相似文献
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