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941.
942.
Changeover delay and concurrent schedules: some effects on relative performance measures 总被引:16,自引:16,他引:0
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Richard L. Shull Stanley S. Pliskoff 《Journal of the experimental analysis of behavior》1967,10(6):517-527
The pigeon and the rat partition total response output between both schedules of a concurrent variable-interval pair. The quantitative nature of a partition seems critically dependent on the relative rates with which the two schedules provide reinforcements for responding, in addition to the changeover delay. The manner in which the changeover delay controls the partition was studied by varying the duration of the changeover delay from 0 to 20 sec with each of two pairs of concurrent variable-interval schedules, viz., Conc VI 1.5-min VI 1.5-min and Conc VI 1-min VI 3-min. Rats served as the subjects and brain stimulation was employed as the reinforcer. When the schedules were Conc VI 1.5-min VI 1.5-min, relative response rate approximated 0.50 at all values of the changeover delay. When the schedules were Conc VI 1-min VI 3-min, relative response rate, computed with respect to the VI 1-min schedule, increased when the duration of the changeover delay increased. Changeover rate decreased when the duration of the changeover delay increased. The decrease was the same for both VI schedules of the Conc VI 1.5-min VI 1.5-min pair but was more rapid for the VI 3-min schedule of the Conc VI 1-min VI 3-min pair. 相似文献
943.
Arm weight, adaptation,and weight discrimination 总被引:1,自引:0,他引:1
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F. Craig Johnson 《Journal of counseling and development : JCD》1967,45(6):589-592
Over 18,000 students at Michigan State University reported their attendance at 46 campus events. Student characteristics were analyzed in terms of student attendance patterns. The 46 events were grouped into 4 independent categories that were attended by students with different characteristics. Students who attended cultural events were mostly single upperclassmen majoring in liberal arts; musical events were attended mostly by music majors; those attending athletic events tended to be single male undergraduates from the more applied disciplines; and social events were attended mostly by undergraduate girls. 相似文献
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Curves of mean percentages of the four gustatory quality responses as a function of concentration of solutions of LiCl, KCl, lithium sulfate, and potassium sulfate were evaluated as to the relative contributions of the cation and anion to the quality. It was concluded that chloride ion, and sulfate ion to a lesser degree, were responsible for the salty quality. In the mid-range concentrations, potassium ion was responsible for the bitter quality, and lithium ion, by means of an ion-soliient interaction; was responsible for the sour quality reported. At the very low concentrations, at which all salts tested evoked sweet responses, a structure produced by a solvent-cation interaction was assumed to be responsible. The details of the presumed structure are still to be clarified. Although one ion in each salt is primarily responsible for a particular quality over a given concentration, the other ion usually modifies the effect. 相似文献