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251.
In the last few years, a number of asymptotic results for the distribution of unrotated and rotated factor loadings have been given. This paper investigates the validity of some of these results based on simulation techniques. In particular, it looks at principal component extraction and quartimax rotation on a problem with 13 variables. The indication is that the asymptotic results are quite good. 相似文献
252.
The implementation of behavior modification techniques in school settings often relies on effective training of teachers as mediators. At the conclusion of Phase I, the performance of an experimental group of 13 teachers who were taught behavior modification by means of an inservice workshop was compared with a no-treatment control group. Although the experimental group scored higher on a paper-and-pencil test of behavior modification, there were no differences between the two groups on selected observed in-class behaviors. During Phase II, half of the experimental group of teachers received two hours of bug-in-the-ear (BIE) training in their own classrooms. BIE resulted in changes in the classroom behaviors of praise and contingency statements. These results are discussed in terms of the situation and response mode specificity of behavior and in terms of the implications for future workshops and research. 相似文献
253.
Charles P. O’Brien Thomas Testa Thomas J. O’Brien Robert Greenstein 《Integrative psychological & behavioral science》1976,11(4):195-202
Eight volunteers maintained on daily methadone participated in a classical conditioning procedure to determine which if any of the elements of narcotic withdrawal could be conditioned. The unconditioned stimulus was the injection of a small dose of naloxone. The unconditioned response was a brief precipitated withdrawal syndrome. The conditioning stimulus was a tone, odor, and injection of saline. Conditioning was successful in the pilot study in 5 of 8 subjects. The conditioned response consisted of tearing, yawning, lacrimation, systolic blood pressure increase, respiratory irregularities and subjective feelings of narcotic withdrawal sickness (nausea, muscle aches, chills). A second group of 8 subjects showed, in addition to the above, evidence of conditioning of heart rate, respiratory rate and skin temperature decrease. These laboratory findings support the clinical reports of a conditioned withdrawal syndrome and suggest ways to improve treatment results by detecting and extinguishing or modifying conditioned responses. 相似文献
254.
Three experiments investigated the effect of stimulus probability on same-different classification time. In Experiments I and II, subjects made same responses on the basis of name matches of simultaneously presented letters. Half of the same trials involved letters that were also physically identical. Experiment I showed that the presentation probability of specific letters affected name matches and different responses, but not physical matches. Experiment II varied stimulus contrast as well as probability. Contrast had a main effect but did not interact with probability at any level of processing. In Experiment III, subjects were switched to the physical level of processing. Stimuli that now had the same name but differed in case were called different. In this condition, the probability effects obs(irved in Experiment II disappeared. These results are interpreted as demonstrating that stimulus probability has its effect during the process that derives the name of the stimulus from the visual representation. This process takes place before the name comparison is made, and the name comparison process precedes the determination of the different response. 相似文献
255.
Joseph E. O. Newton John L. Chapin Oddist D. Murphree 《Integrative psychological & behavioral science》1976,11(2):105-120
Methylphenidate, 0.5 mg/kg, injected intravenously, was used in 10 normal (A line) and 10 genetically nervous (E line) dogs
in a blind-design experiment to aid in prediction, from cardiovascular recordings alone, of behavioral normalityversus nervousness. The prediction was 75 per cent correct, based on heart rate (HR), form of the electrocardiogram (EKG), pattern
of sinus arrhythmia, and pattern of HR response to methylphenidate. Nervous dogs were found to have slower baseline HR’s,
delayed return of HR to baseline after methylphenidate, greater occurrence of baseline EKG abnormalities and much greater
frequency of these after methylphenidate. Degree of nervousness was found to correlate rather highly (1)negatively with baseline HR level, (2)negatively with speed of BP response, and (3)positively with frequency of some of the EKG manifestations. These data, indicative of a relative inertness of physiological functions
of nervous pointer dogs compared with normal pointers, are consistent with the behavioral and some of the biochemical findings
previously reported. 相似文献
256.
It was shown that a McCollough-type color aftereffect could be induced using a pair of patterns each of which contained lines of many orientations (radial lines and concentric circles). That is, the two patterns appear to be color adapted independently. The effect could simply be a new version of the McCollough effect facilitated by a tendency to fixate the centers of the patterns. Also, the size features of the displays could be used as the basis of a spatial frequency analyzer explanation. Experimental data were used to test both of these suggestions, but very little support was found for either. It was therefore suggested that the major basis of the effect was the color adaptation of “curvature analyzers.” 相似文献
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