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171.
The minimal transformation to orthonormality   总被引:1,自引:0,他引:1  
The solution is presented to the problem of finding that orthonormal matrix closest in the least-square sense to a given matrix of full rank. An application is shown to the problem in multiple regression analysis of determining the importance of each independent variable.  相似文献   
172.
The relationship between the occupational preferences of 147 superior students and their fathers' occupations was traced over the 4-year period that the students attended high schools in Wisconsin. Analysis of the data indicated that both male and female superior students tended to state vocational preferences at the professional level early in high school and to maintain this preference throughout. Their occupational preferences were generally at a higher level than those of their fathers. There was no trend away from general preferences for work at a professional level toward naming of specific occupations within that level. The results suggest that theories of vocational development that imply that stages are passed through during later adolescent periods do not apply to the superior student population of this study.  相似文献   
173.
In 11 male albino rats, lever-pressing responses, maintained under a CRF escape schedule with light as the aversive stimulus, were examined at each of five intensities, viz., 2.5, 18, 105, 190, and 386 ft-C. The function relating reciprocal of latency of the escape response to aversive light intensity passed through a maximum.  相似文献   
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Crises and critical life transitions activate 2 distinct but complementary modes of coping, (a) transforming developmental circumstances in accordance with personal preferences (assimilative tendency) and (b) adjusting personal preferences to situational constraints (accommodative tendency). Assimilative and accommodative tendencies were measured by a questionnaire comprising 2 independent scales (Tenacious Goal Pursuit and Flexible Goal Adjustment). Both scales predict high life satisfaction and low depression and are positively related to generalized internal control beliefs. The scales evinced an opposite relation to age: Cross-sectional analyses on a sample of 890 Ss in the age range from 34 to 63 years revealed a gradual shift from an assimilative to an accommodative mode of coping. Implications for theories of depression and successful aging are discussed.  相似文献   
176.
Graphic designers and an experimental psychologist worked together to improve the design of two map symbols which are frequently confused: the symbols for cuttings and embankments on topographic maps. The problem was analysed in terms of the function of the symbols and their likely cognitive representations. Tests were developed to evaluate alternative designs, including an intervisibility task which requirred users to visualize the landform from the symbols viewed in the context of a map. Tests were given to schoolchildren and to experienced map users in order to compare the standard symbols with five alternative designs. Children's performance was strongly affected by the symbols they used, but experienced users were much less affected. After some refinement of the symbols a further experiment demonstrated the superiority of a number of alternative designs over the existing symbols on a range of test: scores were almost double on the intervisibility task. The paper makes recommendations to cartographers and argues for greater consideration of the inexperienced map user in the design process.  相似文献   
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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   
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