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981.
The CFF was determined with three sectored disks, each of which corresponded to one of the three rings in a Helmholtz disk. The fusion frequency is identical for all three rings of a Helmholtz disk but with the three sectored disks it was found that the rate of stimulus occlusion is a major factor in determining the CFF. It was tentatively concluded that the effect was not a consequence of different stimulus wave-forms. The phenomenon appears to have been reported late in the last century. 相似文献
982.
C. R. Ingils 《Journal of counseling and development : JCD》1968,46(8):744-748
In our society an increasingly greater emphasis is being placed on group interaction and decision-making. Persons participating in such a process often use the term “group dynamics” to describe what is thought to be a social-psychological phenomenon. This article discusses some of the elements of “true” group characteristics and effects, and their possible existence in “group dynamic” situations. The article also deals with the implications of the effects of these elements in “group dynamic” environments on educational and administrative leadership and decision-making. 相似文献
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985.
Human subjects were intermittently reinforced with money for performing correctly on a conditional matching-to-sample task. The matching performance was examined as a function of a) the duration of Time-Outs (TOs) which followed every incorrect response and b) the frequency (FR value) with which TOs followed incorrect responses. The matching accuracy increased with longer TOs and decreased with less frequent presentation of TOs. 相似文献
986.
Of 23 pigeons, 11 received continuous reinforcement for key pecking, and 12 received an FR 10 schedule of reinforcement. The birds were then tested without food, but with potential conditioned reinforcers presented either on the same schedule as in training, on the other schedule, or not at all. Each bird in the subgroup trained on CRF and tested with Sr's at FR 10 not only gave more responses in testing than did each bird in both subgroups receiving no Sr's, but also gave more responses than did each bird in the Sr subgroup receiving CRF training and Sr's at CRF. Cumulative records are presented to show the effects of different schedules of conditioned reinforcers. 相似文献
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Shimp CP 《Journal of the experimental analysis of behavior》1967,10(1):57-65
When a pigeon's choices between two keys are probabilistically reinforced, as in discrete trial probability learning procedures and in concurrent variable-interval schedules, the bird tends to maximize, or to choose the alternative with the higher probability of reinforcement. In concurrent variable-interval schedules, steady-state matching, which is an approximate equality between the relative frequency of a response and the relative frequency of reinforcement of that response, has previously been obtained only as a consequence of maximizing. In the present experiment, maximizing was impossible. A choice of one of two keys was reinforced only if it formed, together with the three preceding choices, the sequence of four successive choices that had occurred least often. This sequence was determined by a Bernoulli-trials process with parameter p. Each of three pigeons matched when p was ½ or ¼. Therefore, steady-state matching by individual birds is not always a consequence of maximizing. Choice probability varied between successive reinforcements, and sequential statistics revealed dependencies which were adequately described by a Bernoulli-trials process with p depending on the time since the preceding reinforcement. 相似文献