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71.
Guttman's index of indeterminacy (22 – 1) measures the potential amount of uncertainty in picking the right alternative interpretation for a factor. When alternative solutions for a factor are equally likely to be correct, then the squared multiple correlation 2 for predicting the factor from the observed variables is the average correlation AB between independently selected alternative solutionsA andB, while var ( AB )=(1 – 2)2/s, wheres is the dimensionality of the space in which unpredicted components of alternative solutions are to be found. When alternative solutions for the factor are not equally likely to be chosen, 2 is the lower bound for E( AB ); however, E( AB ) need not be a modal value in the distribution of AB . Guttman's index and E( AB ) measure different aspects of the same indeterminacy problem.  相似文献   
72.
The associations formed in the components of a multiple schedule can be classified as (1) stimulus-response (S-R) associations and (2) stimulus-reinforcer (S-SR) associations. The present experiments sought to determine the individual contribution of these S-R and S-SR associations to stimulus control by manipulating them independently. Responses postponed shocks by 25 sec in the presence of a tone alone and a light alone in all experiments. The contingencies programmed in the absence of both tone and light established a reference for the S-R and S-SR associations in tone and in light. All four possible combinations of signalling response increase or decrease together with incentive increase or decrease were studied. Although the influence of the contingencies operating in the absence of tone and light was difficult to detect from response rates in tone or light, presenting tone and light together revealed clear effects. Response rates in tone and light together relative to those in either alone depended upon the contingency operating in the absence of tone and light. Stimulus-response and stimulus-reinforcer associations appeared to counteract each other when in opposition and combine together to enhance each other when in agreement. This suggested that the associations of a stimulus to response and to incentive combine algebraically in determining stimulus control. An algebraic analysis in terms of the S-R and S-SR associations conditioned to the stimulus elements comprising the training and test stimuli accounted for the observed patterns of data.  相似文献   
73.
Subjects were assigned to use either three or six categories and were given either 5 or 10 trials in a word-sorting task. Subsequent to sorting, they recalled as many words as they could. A measure of sorting consistency showed that the six-category sort was a more difficult task than was the three-category sort. Number of categories did not have a significant effect on recall performance regardless of whether 5 or 10 sorting trials were used. A correlational analysis raised questions about the relationship of the sorting tasks to recall performance and clustering.  相似文献   
74.
Male hooded and albino rats were exposed to a light flash followed at various temporal intervals by a startle-eliciting 117 db. (re 20 muN/m2) burst of white noise. The visual stimulus engendered startle response inhibition (maximally when the lead time was 64-250 msec) as well as startle response latency reduction (maximally when the lead time was 2-8 msec). The temporal functions for the effects of visual stimuli paralleled those previously reported for startle modification by acoustic events. Further study revealed that, given optimal lead times, inhibition is produced reliably by weaker visual stimuli (3 X 10-6 cd-sec/cm2) than latency reduction (3 X 10-4 cd-sec/cm2). This differential sensitivity to visual stimuli is also analogous to previously reported findings for events in the acoustic environment. It reveals that the neural mechanisms that mediate latency reduction and inhibition can be engaged by either acoustic or visual stimulation.  相似文献   
75.
The present study compared the WISC and WISC-R on a group of psychiatric adolescent inpatients. The results indicated high intercorrelations between the two test versions but with the correlations linearly related to the changes in content and administration rules of the WISC-R. Analyses of variance indicated that, on the basis of the Full Scale IQ, the WISC is an easier test than the WISC-R.The authors gratefully acknowledge the assistance of Ms. Kathleen Lennox for her aid in data analysis and computer programming.  相似文献   
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Fifteen hermaphroditic females with the adrenogenital syndrome received corrective, androgen-suppressing therapy with cortisone from birth onward. They were studied psychologically in late adolescence and adulthood, with particular attention to a possible long-term effect of fetal androgenization on aggressive manifestations. No such effect was evident. The girls were tomboyish in the manner previously reported for the adrenogenital syndrome.  相似文献   
79.
Forty-six female mice (CFW) were isolated for a period of 23 weeks. The effect of isolation on fighting behavior was tested weekly by introducing a naive brown female mouse into the subject's home cage. Total leucocyte counts were obtained at 8 and 14 weeks of isolation. The appearance of leucopenia was used as an index of elevated adrenocortical activity. After 23 weeks of isolation all animals were sacrificed by decapitation. Plasma was collected for corticosterone assay, and paired adrenals were used to assay catecholamine levels. On the basis of the frequency and/or the absence of fighting, the mice were segregated into fighters (n = 22) and non-fighters (n = 17). Analysis of the data by Pearson's product moment correlation and Student's t-test showed that elevated sympathetic-adrenal activity was positively correlated with aggression and that elevated adrenocortical activity was negatively correlated with aggression.  相似文献   
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