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91.
Some clarifications of the CANDECOMP algorithm applied to INDSCAL   总被引:2,自引:0,他引:2  
Carroll and Chang have claimed that CANDECOMP applied to symmetric matrices yields equivalent coordinate matrices, as needed for INDSCAL. Although this claim has appeared to be valid for all practical purposes, it has gone without a rigorous mathematical footing. The purpose of the present paper is to clarify CANDECOMP in this respect. It is shown that equivalent coordinate matrices are not granted at global minima when the symmetric matrices are not Gramian, or when these matrices are Gramian but the solution not globally optimal.Part of this research has been supported by The Netherlands Organization for Scientific Research (NWO), PSYCHON-grant (560-267-011).  相似文献   
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This research examined the extent to which the personality characteristics of agency and communion are sex linked, and the extent to which differences in these orientations can account for sex differences in reward distribution behavior. In two studies, the agency and communion level of large samples of male and female undergraduates were assessed. As expected, males were more agentic and females were more communal. Moreover, when subjects who scored high or low on agency and high or low on communion were asked to allocate rewards between themselves and a co-worker, these personality differences were related to their allocation decisions. These results were used as the basis for discussing the role that sex-linked personality differences might play in distributive justice judgments.This article is an adaptation of a colloquium presentation at the meeting of the American Psychological Association, Los Angeles, August 1981. The research reported here was supported by NIMH grant MH29987-1, Goals, Motives, and Norms of Reward Distribution, and by NIMH Biomedical Research Support Grant from the College of Social Science, Michigan State University. The authors wish to thank Andrea Doughty for her valuable advice, and to gratefully acknowledge the help of Mark Teicher, Julie B. Klein, Sue Schnelbach, Pat Loepp, Barb Allen, Gavin Goodrich, Bob O'Hara, Kelly Bowen, Rod Hollenstein, Steve Schultz, and Mary Hurst.  相似文献   
94.
It was found that illiterate adults could neither delete nor add a phone at the beginning of a non-word; but these tasks were rather easily performed by people with similar environment and childhood experiences, who learned to read rudimentarily as adults. Awareness of speech as a sequence of phones is thus not attained spontaneously in the course of general cognitive growth, but demands some specific training, which, for most persons, is probably provided by learning to read in the alphabetic system.  相似文献   
95.
A developmental ‘lag’ is found in the Conservation of Quantity (Liquids) in a sample of 73 rural, schooled Baoulé children (Ivory Coast, West Africa) aged 7 to 14 years. This study was designed to investigate if this ‘lag’ could be reduced or bridged through training and whether it could be attributed to differences in ‘performance’ or in ‘competence’. A sub-sample of 28 children aged 7 to 9 years was divided into two matched groups, one being trained for Conservation of Liquids and the other for Class Inclusion (Lavallée and Dasen in press). Statistically significant training effects were observed, which generalized to other concrete operational concepts and remained stable over at least one month. Since no ‘actualization’ or very fast learning occurred, the ‘lag’ was attributed to differences in competence; the training was sufficient to bridge the developmental lag.  相似文献   
96.
Psychotropic drugs such as methadone, morphine and bulbocapnine produce increments in dopamine metabolism as an unconditioned reflex. When a buzzer noise is used as a conditioned stimulus (CS) with these drugs as unconditioned stimuli, the buzzer CS acquires the properties of the drugs in increasing dopamine metabolism. These results suggest that the brain, like other visceral organs, can be conditioned in terms of neurotransmitter release or metabolism.  相似文献   
97.
We have described a series of 26 cases of cortical lesions in children from 312 to 15 years of age (17 left-sided, six right-sided, three bilateral), in which 19 had varying degrees of language disturbance. We have attempted to establish the nature and evolution of these aphasic disorders, and have compared our observations to those previously published. Our analysis appears to indicate a relative hemispheric equipotentiality which permits the transfer of language representation to the opposite hemisphere in the case of a unilateral lesions in childhood. This conclusion, however, has at least the appearance of being in conflict with other reported findings, viz., those deriving from psychometric testing of subjects with unilateral perinatal lesions; and those concerning studies of fetal and newborn brains which suggest a very early, if not innate, hemispheric specialization.The fact of this discrepancy has lead us to reconsider the concept of a critical period as defined by Lenneberg. In this respect, we have also discussed the possibility of a partial transfer of language representation, of an intrahemispheric reorganization by intact “uncommitted” areas (P. Goldman), and finally, the need for an adequate stimulus during a given period in order for a preformed area to become functional.  相似文献   
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Since Pavlov, theories of conditioning have assumed that CR evocation is governed by a series of internal stimuli generated by the CS. This hypothesis was tested in conditioning of the rabbit's nictitating membrane (NM) response by attempting to manipulate the internal sequence through truncating a delay CS and extending a trace CS on test trials. These perturbations of CS duration produced large deficits in CR likelihood and smaller alterations in the CR's time course. As predicted by many models of conditioning, the onset of the CS appeared to play a large but not exclusive role compared to CS duration and CS offset in both evocation and timing of the CR. The results are discussed with respect to their implications for real-time models of conditioning.  相似文献   
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