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251.
Pigeons were punished with mild shock for pecking during one of two components of a multiple schedule. They eventually recovered so that they pecked at the same rate during both components. In one experiment they were extinguished after recovering. When punishment was maintained during extinction, they extinguished faster during the punished, than during the unpunished component. When punishment was stopped during extinction, they extinguished faster during the unpunished than during the previously punished component. In another experiment, punishment was programmed first during neither of the two components, then during one, then during both, and finally during the other component. The extent of recovery decreased with each successive cycle. It is concluded that, if transient emotional states are ignored, reward and punishment are symmetrical in their effects.  相似文献   
252.
Monkeys' performance on ambiguous-cue problems   总被引:1,自引:0,他引:1  
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256.
Factor analysis by minimizing residuals (minres)   总被引:1,自引:0,他引:1  
This paper is addressed to the classical problem of estimating factor loadings under the condition that the sum of squares of off-diagonal residuals be minimized. Communalities consistent with this criterion are produced as a by-product. The experimental work included several alternative algorithms before a highly efficient method was developed. The final procedure is illustrated with a numerical example. Some relationships of minres to principal-factor analysis and maximum-likelihood factor estimates are discussed, and several unresolved problems are pointed out.The authors wish to thank the Factor Analysis Work Group (supported, in part, by ONR) for valuable criticisms and suggestions made in the course of a discussion of the present work in April, 1965.  相似文献   
257.
This annual review of job satisfaction researches is the 23rd in a series and covers reports published in 1964–65 plus earlier studies not previously dealt with in this journal. The format—findings and conclusions, topics investigated, per cent dissatisfied, current emphases, and summaries of studies—has become standard in this series of articles.  相似文献   
258.
The present experiment sought to determine whether individual Ss tend to employ repeatedly the same response patterns in binary choice tasks containing nondiscriminable stimuli and, if so, whether the response sequences when used to constructstimulus sequences improve the performance of other choice tasks. Information and frequency analyses of the response sequences of 48 Ss showed moderate consistency of patterning within a light and within a tone task. Performance of a card task following the light and tone tasks was closely related to the task (light or tone) from which the stimulus sequence was obtained. The frequency analysis showed that repetition patterns were preferred by most Ss but at the expense of alternation responses. The presentation of reinforcement in the card task did not improve performance over that observed in the light and tone tasks.  相似文献   
259.
In a two-choice situation with event-probabilities of 0.67 and 0.33, recency effects were studied as a function of (a) event-dependence and (b) fore-knowledge of event-probabilities. The following conclusions are drawn: (1) Belief in some kind of event-dependence is a necessary condition for the occurrence of negative recency; (2) Foreknowledge of the event-probabilities does not affect recency phenomena; (3) The behaviour of subjects in the two-choice situation, is less irrational than some writers have claimed.  相似文献   
260.
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