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931.
A subsample of 814 sexually experienced adolescent females from the 1979 U.S. National Survey of Young Women was analyzed to assess the correlates of age at 1st sexual intercourse. Multiple regression procedures were used to examine sets of variables sequentially. In the hierarchical regression model, the control variables (respondent's age, race, religion, and age at menarche), along with 3 independent variables (household income, ideal age at 1st marriage, and ideal age for 1st birth), predicted age at 1st intercourse. The control variables accounted for a major portion of the variance in the model. Of the controls, chronological age and age at menarche were highly significant across all models tested.  相似文献   
932.
933.
INFANTS' PERCEPTION OF PHRASE STRUCTURE IN MUSIC   总被引:1,自引:0,他引:1  
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935.
936.
The right hand hemisphere of the brain is purported to be the seat of the perceptual, intuitive, synthetic, visual and non-rational activities. In it is believed to reside the creative ability. Evidence is presented which suggests that, by exercising specifically the right hand hemisphere using a series of carefully structured tasks, some aspects of creative behaviour can be enhanced. It follows that users of creativity training courses should not expect every aspect of creative behaviour to be enhanced by any given course.  相似文献   
937.
The author discusses the impact of the Holocaust on both the children of victims and victimizers and reports on empirical researches conducted among Israeli student health professionals and others as to how ready they, the people of the victims, are to approve of and to participate in various programs and events which take the lives of helpless others, and reports disturbing results. He concludes that making a commitment to human life is the single most important task for all of us.  相似文献   
938.
A new approach is described for the development and structure of perceptual knowledge-based systems. This systematic method for acquiring perceptual knowledge for use in knowledge-based systems and for representing perceptual knowledge within the systems has revealed that two broad classes of perceptual activity can each be characterized by a single logical operator. The number of rules necessary to accomplish particular perceptual tasks can also be estimated.  相似文献   
939.
The statistical simulation program DATASIM is designed to conduct large-scale sampling experiments on microcomputers. Monte Carlo procedures are used to investigate the Type I and Type II error rates for statistical tests when one or more assumptions are systematically violated-assumptions, for example, regarding normality, homogeneity of variance or covariance, mini-mum expected cell frequencies, and the like. In the present paper, we report several initial tests of the data-generating algorithms employed by DATASIM. The results indicate that the uniform and standard normal deviate generators perform satisfactorily. Furthermore, Kolmogorov-Smirnov tests show that the sampling distributions ofz, t, F, χ2, andr generated by DATASIM simulations follow the appropriate theoretical distributions. Finally, estimates of Type I error rates obtained by DATASIM under various patterns of violations of assumptions are in close agreement with the results of previous analytical and empirical studies; These converging lines of evidence suggest that DATASIM may well prove to be a reliable and productive tool for conducting statistical simulation research.  相似文献   
940.
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