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Practice in front of a mirror is a common procedure for activities such as dance, gymnastics, and other sports. The purpose of this study was to examine the effect that performing with concurrent visual feedback from a mirror had on the acquisition of the power clean movement. 18 college-age males who had no prior experience with the power clean movement served as subjects who were assigned to one of two groups. One group had use of a mirror during the practice trials and the other practiced without the mirror. All subjects viewed an instructional videotape and had practice trials. All subjects were evaluated for proper technique on a pretest, a posttest without the mirror, and a posttest with the mirror. Analysis showed a significant difference between pre- and posttest performances for both groups and a significant difference between groups on the posttest performances with the mirror. Evidently the videotaped instruction was sufficient to allow both groups to improve in performance of the power clean. Differences in posttest performances with the mirror reflected the type of feedback (with or without the mirror) available during training.  相似文献   
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Previous research has suggested that women with a negative emotional orientation toward sexuality (i.e., erotophobia) have difficulty learning and retaining sexually relevant material such as contraceptive information. It has been hypothesized that these women become aroused by this material and that this arousal interferes with their ability to learn it. The importance of this issue led us to conduct the current study. Erotophobic and erotophilic women viewed presentations about contraception while their physiological responses were being monitored. In addition, they were tested on the information contained in the presentation before, immediately after, and again 4-6 weeks after the presentation. The results indicated that the erotophobic women knew less contraceptive information before the presentation and were more aroused by the presentation. This arousal, however, did not interfere with retention of the material. These results are discussed in terms of individual differences in reactions to sexual material and the ability to learn, retain, and use contraceptive information.  相似文献   
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A study was conducted with 104 hospital employees to assess the relationship between pay-for-performance perceptions and pay satisfaction. Unlike previous research examining this relationship, a multi-item measure of pay-for-performance perceptions and a multidimensional measure of pay satisfaction were used. As hypothesized, the results indicated a positive relationship between pay-for-performance perceptions and pay-raise satisfaction, pay-level satisfaction, and overall pay satisfaction even after the effects of salary level, salary increases, performance ratings, job tenure, job satisfaction, and promotions were controlled. The importance of gathering perceptual data on characteristics of the pay system believed to have differential relationships with the subdimensions of pay satisfaction are discussed.  相似文献   
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The IES Arrow-Dot was administered to 41 cocaine detoxification patients. This group's scores indicated lower ego functioning and higher impulsivity and superego functioning than other clinical samples. No significant differences were noted between the Arrow-Dot scores of patients who successfully completed the program and those who did not.  相似文献   
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This paper discusses least squares methods for fitting a reformulation of the general Euclidean model for the external analysis of preference data. The reformulated subject weights refer to a common set of reference vectors for all subjects and hence are comparable across subjects. If the rotation of the stimulus space is fixed, the subject weight estimates in the model are uniquely determined. Weight estimates can be guaranteed nonnegative. While the reformulation is a metric model for single stimulus data, the paper briefly discusses extensions to nonmetric, pairwise, and logistic models. The reformulated model is less general than Carroll's earlier formulation.The author is grateful to Christopher J. Nachtsheim for his helpful suggestions.  相似文献   
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Van de Geer has reviewed various criteria for transforming two or more matrices to maximal agreement, subject to orthogonality constraints. The criteria have applications in the context of matching factor or configuration matrices and in the context of canonical correlation analysis for two or more matrices. The present paper summarizes and gives a unified treatment of fully general computational solutions for two of these criteria, Maxbet and Maxdiff. These solutions will be shown to encompass various well-known methods as special cases. It will be argued that the Maxdiff solution should be preferred to the Maxbet solution whenever the two criteria coincide. Horst's Maxcor method will be shown to lack the property of monotone convergence. Finally, simultaneous and successive versions of the Maxbet and Maxdiff solutions will be treated as special cases of a fully flexible approach where the columns of the rotation matrices are obtained in successive blocks.The author is obliged to Henk Kiers for computational assistance and helpful comments.  相似文献   
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