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891.
Persistence and its assessment have been studied since the 1920s. One common approach in measuring persistence has been through testing the subject's ability to solve difficult or monotonous problems. Another approach has been through questionnaires. Although persistence is very important in academic achievement and in the general development of personality, no questionnaires have been developed for measuring persistence in children. The present research concerns the development of such a scale. It includes 40 items and was tested on 322 Israeli children aged 7-13. The internal reliability of the scale (Cronbach alpha) was .66, and the test-retest reliability after 6 months was .77. The scale differentiated active gymnasts from non-gymnasts as well as persistent gymnasts from dropout gymnasts. In addition, significant correlations were found between the scale and the need-persistence measure of the Rosenzweig Picture Frustration Study, Locus of Control, and other measures. We discuss these findings along with the significance of persistence in everyday life.  相似文献   
892.
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior.  相似文献   
893.
A within-subjects comparison was made of pigeons' performance on two temporal discrimination procedures that were signaled by differently colored keylight samples. During stimulus trials, a peck on the key displaying a slanted line was reinforced following short keylight samples, and a peck on the key displaying a horizontal line was reinforced following long keylight samples, regardless of the location of the stimuli on those two choice keys. During position trials, a peck on the left key was reinforced following short keylight samples and a peck on the right key was reinforced following long keylight samples, regardless of which line stimulus appeared on the correct key. Thus, on stimulus trials, the correct choice key could not be discriminated prior to the presentation of the test stimuli, whereas on position trials, the correct choice key could be discriminated during the presentation of the sample stimulus. During Phase 1, with a 0-s delay between sample and choice stimuli, discrimination learning was faster on position trials than on stimulus trials for all 4 birds. During Phase 2, 0-, 0.5-, and 1.0-s delays produced differential loss of stimulus control under the two tasks for 2 birds. Response patterns during the delay intervals provided some evidence for differential mediation of the two delayed discriminations. These between-task differences suggest that the same processes may not mediate performance in each.  相似文献   
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