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921.
Temporal control of behavior: schedule interactions   总被引:1,自引:1,他引:0       下载免费PDF全文
In Experiment I the response that terminated the postreinforcement pauses occurring under a fixed-interval 60-second schedule was reinforced, if the pause duration exceeded 30 seconds. The percentage of such pauses, rather than increasing, decreased. There were complex effects on the discriminative control of the pause by the reinforcer terminating the previous fixed interval, depending on whether the fixed interval and the added reinforcer were the same or different. In Experiments II(a) and II(b), each reinforcement initiated an alternative fixed-interval interresponse-time-greater-than-t-sec schedule, the schedule values being systematically varied. When the response following a pause exceeding a given duration was reinforced, fewer such pauses occurred than when they were not reinforced, i.e., on the comparable simple fixed-interval schedule. There was no systematic relationship between mean interrinforcement interval and duration of the postreinforcement pause. The pause duration initiated by reinforcement was directly related to the dependency controlling the shortest pause at that time, regardless of changes in mean interreinforcement interval.  相似文献   
922.
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924.
30 elderly subjects were matched with 30 young subjects and tested on a kinesthetic short-term memory task which required the replication of criterion moves after a variable retention interval under conditions of either rest, differing interpolated movement tasks, or mental activity. A visual control condition was used. Differing interference and temporal decrements were observed. Both old and young subjects differed significantly between sighted and blindfold conditions; however, there was no difference between the performance of the old and the young in the blindfold (kinesthetic) condition. These findings were discussed with respect to practical implications for the retraining of old subjects on certain motor tasks.  相似文献   
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926.
A multiple-answer multiple-choice test item has a certain number of alternatives,any number of which might be keyed. The examinee is also allowed to mark any number of alternatives. This increased flexibility over the one keyed alternative case is useful in practice but raises questions about appropriate scoring rules. In this article a certain class of item scoring rules called thebinary class is considered. The concepts ofstandard scoring rules and equivalence among these scoring rules are introduced in the misinformation model for which the traditional knowledge model is a special case. The examinee's strategy with respect to a scoring rule is examined. The critical role of a quantity called the scoring ratio is emphasized. In the case of examinee uncertainty about the number of correct alternatives on an item, a Bayes and a minimax strategy for the examinee are developed. Also an appropriate response for the examiner to the minimax strategy is outlined.Research partially supported under Grants N00014-67-A-0314-0022 from the Office of Naval Research and GS-32514 and MPS 75-07539 from the National Science Foundation.  相似文献   
927.
Summary Two experiments were performed to determine whether a physiological correlate of visual imagery could be measured from visually-evoked-responses (VERs). High and Low imagery groups were used. There was no direct effect of imagery, although some differences between the groups emerged. These differences are thought to be due to factors associated with imaging, but not imagery per se.  相似文献   
928.
Literature on sex differences in impulsivity has tended to focus on differences between groups, while ignoring relationships beyond zero order correlations. The purpose of this study was to evaluate Maccoby's hypothesis (1966) of opposite-direction correlations where the relationship between a set of variables (e.g., impulsivity and intellectual ability) is curvilinear, with males and females being systematically distributed on opposite sides of the curve. The Primary Mental Abilities (PMA) and Matching Familiar Figures tests were administered to 44 males and 49 females. The relationship between all of the PMA subtests and impulsivity was curvilinear for males, but linear for females on all but one of the subtests. The importance and implications of examining distribution differences rather than group differences are discussed.Support for this study has come from the Office of Research Administration, University of Kansas, Grant Number 3581-5038. This paper was presented in part at the meeting of the American Psychological Association, Chicago, August 1975, Division 7.  相似文献   
929.
Levin's suggestion that internal feedback strategies be employed in judgmental and learning tasks is discussed. The predictions of an internal feedback notion are seen as inconsistent with Veit's ratio and difference task data. Scale-free frameworks and scale-convergence criteria used in previous research are described as useful techniques for separating integration from judgmental processes in information-integration as well as learning-task situations.  相似文献   
930.
In Experiment 1, high and low test-anxious subjects recalled a list composed of words that could be organized either by taxonomic categories or first letters. High-anxiety subjects showed less recall and conceptual clustering. There was no anxiety difference in alphabetic clustering, but low-anxiety subjects used alphabetic clusters to bridge transitions between conceptual categories more often than did high-anxiety subjects. An initial orienting task which required semantic processing reduced the recall deficit for high-anxiety subjects but not the clustering deficit. Low-anxiety subjects seemed minimally affected by a nonsemantic-orienting task. Experiment 2 used a list that could be organized by associates or rhymes. High-anxiety subjects recalled less and exhibited less clustering of both types. The nonsemantic-orienting task depressed performance for both anxiety levels, though the effect was somewhat greater for high-anxiety subjects. Overall, these results provide little evidence to support the hypothesis that high-anxiety subjects process differently only for semantic content, but methodological limitations preclude unequivocally rejecting that view.  相似文献   
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