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Life is not breath, but action; to live is to make use of our organs, our senses, our faculties, every part of ourselves which gives us the feeling of our own existence. Rousseau Emile  相似文献   
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Within the context of a prospective longitudinal research design, the structure of personality and initial levels of drug use were used to predict, multivariately, later drug use among male and female adolescents. The findings indicated that personality and belief measures of nonconventionality provide a significant increment in the prediction of later drug use beyond a level achieved by knowing initial usage rates. In addition, other personality and belief measures yield further increments in the prediction of subsequent drug use. Developmentally, the results revealed a differentiation of drug use patterns across the year's time, with one pattern primarily reflecting alcohol use, and a second pattern primarily reflecting use of marijuana and ‘hard’ drugs. While both patterns were related to measures of nonconventionality, certain personality features distinguished between them. Emergent use of marijuana and ‘hard’ drugs was related to depression, mistrust and attractiveness, while emergent alcohol use was related to generosity, ambition, agility and cheerfulness. These results were cross-validated in two samples of subjects. Implications of the findings for adolescent psychosocial development are discussed.  相似文献   
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Kamin (1980) has contended that arguments presented in Wolff (1979) are too weak to justify “resuscitating the selective migration debate.” Although Kamin's (1980) critique points up the need for closer scrutiny of the cumulative-deficit phenomenon, it fails to refute Wolff's (1979) conclusion that selective migration is partly responsible for the North-South black IQ differential.  相似文献   
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This study investigated the effects of presumably positive and neutral response-contingent stimuli on the occurence of stuttering. Eight adult stutterers spoke spontaneously during a 60-min experimental session, which was divided into three 20-min periods. During Condition I no stimuli were delivered. During Condition II a digital counter and a pair of yellow lights were activated each time the subject stuttered. During Condition III these same response-contingent stimuli were delivered, but with the additional factor that the subject would earn 5¢ each time the counter moved forward and the lights were illuminated. Conditions II and III were counterbalanced across subjects. The experimenter was unaware of which of the two contingencies were operative during Conditions II and III. Results showed no significant changes in occurence of stuttering due to either response-contingent stimulus. A discussion of theoretical and experimental implications is given.  相似文献   
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In this study of psychotic persons in a peasant society, there was a significant attrition in important social network structure after the onset of psychosis. The difficulties involved in providing non-reciprocal social support is noted, yet modest social support of functions may be critical.This work was supported by the National Institute of Mental Health (grant Number 1 R01 MH34322-01). Acknowledgement is expressed to Dr. Phim and Mr. Phimpha for their assistance with data collection, and to Dr. Robert Zimmerman and Ms. Beth Stone for their assistance with data tabulation and analysis.  相似文献   
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We present a new model and associated algorithm, INDCLUS, that generalizes the Shepard-Arabie ADCLUS (ADditive CLUStering) model and the MAPCLUS algorithm, so as to represent in a clustering solution individual differences among subjects or other sources of data. Like MAPCLUS, the INDCLUS generalization utilizes an alternating least squares method combined with a mathematical programming optimization procedure based on a penalty function approach to impose discrete (0,1) constraints on parameters defining cluster membership. All subjects in an INDCLUS analysis are assumed to have a common set of clusters, which are differentially weighted by subjects in order to portray individual differences. As such, INDCLUS provides a (discrete) clustering counterpart to the Carroll-Chang INDSCAL model for (continuous) spatial representations. Finally, we consider possible generalizations of the INDCLUS model and algorithm.We are indebted to Seymour Rosenberg for making available the data from Rosenberg and Kim [1975]. Also, this work has benefited from the observations of S. A. Boorman, W. S. DeSarbo, G. Furnas, P. E. Green, L. J. Hubert, L. E. Jones, J. B. Kruskal, S. Pruzansky, D. Schmittlein, E. J. Shoben, S. D. Soli, and anonymous referees.This research was supported in part by NSF Grant SES82 00441, LEAA Grant 78-NI-AX-0142, and NSF Grant SES80 04815.  相似文献   
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