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921.
The effect of several reinforcement schedules on the variability in topography of a pigeon's key-peck response was determined. The measure of topography was the location of a key peck within a 10-in. wide by 0.75-in. high response key. Food reinforcement was presented from a magazine located below the center of the response key. Variability in response locus decreased to a low value during training in which each response produced reinforcement. Variability increased when fixed intervals, variable intervals, random intervals, or extinction were scheduled.  相似文献   
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Three samples, each divided into males and females, were asked to indicate to what degree some job characteristics were important to them. The job characteristics represented both intrinsic and extrinsic factors. In the first sample (40 male and 44 female university students) there was no sex difference in job orientation. Both selected the intrinsic factors more than the extrinsic factors. There was also no sex difference in the second sample, which consisted of 68 male and 33 female public school teachers. They, however, stressed as many intrinsic factors as extrinsic. The general results of the third sample showed significant sex differences. The sample of 259 male and 143 female employees represented a technical division of a large service-oriented organization. Education and job level were significantly different for the two subgroups. When these two variables were controlled for a sample of clerks and of first-level supervisors, no sex difference appeared in job orientation. The results also showed that the higher the job level, the more intrinsically-oriented the employees were regardless of their sex.  相似文献   
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Subjects tried to recall the location of a tactile stimulus on the underside of the forearm after delays of 0, 3, 5, 10, 15, 30, 45 and 60 sec. When “rehearsal” was prevented by requiring subjects to count backwards during the delay, accuracy of recall decreased systematically reaching an asymptote after 45 sec. When subjects were left free to “rehearse,” this did not affect the decline in accuracy over the first 10 sec. Between 10 and 15 sec. there was a significant increase in accuracy followed by a slow decline which had not reached asymptote by 60 sec. It is suggested that tactile STM (short-term memory) depends on two processes, a fading sensory trace which is unaffected by distraction and a less labile system which does not appear to be verbal but which depends on “rehearsal.”  相似文献   
929.
Procedures are described for the generation, synchronization. and accurate spacing of discrete dichotic stimulation material. A suggested standard definition of interpair interval is proposed.  相似文献   
930.
Threshold elevations (TE) were determined at a testsite on the left thigh with the simultaneous presentation of combinations of maskers positioned on the trunk. It was found that the resultant TE from groups of up to 10 multiple maskers is nearly equal to the addition of the TE produced by each masker separately.  相似文献   
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