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861.
Three-way metric unfolding via alternating weighted least squares   总被引:6,自引:3,他引:3  
Three-way unfolding was developed by DeSarbo (1978) and reported in DeSarbo and Carroll (1980, 1981) as a new model to accommodate the analysis of two-mode three-way data (e.g., nonsymmetric proximities for stimulus objects collected over time) and three-mode, three-way data (e.g., subjects rendering preference judgments for various stimuli in different usage occasions or situations). This paper presents a revised objective function and new algorithm which attempt to prevent the common type of degenerate solutions encountered in typical unfolding analysis. We begin with an introduction of the problem and a review of three-way unfolding. The three-way unfolding model, weighted objective function, and new algorithm are presented. Monte Carlo work via a fractional factorial experimental design is described investigating the effect of several data and model factors on overall algorithm performance. Finally, three applications of the methodology are reported illustrating the flexibility and robustness of the procedure.We wish to thank the editor and reviewers for their insightful comments.  相似文献   
862.
Combinatorial data analysis: Association and partial association   总被引:4,自引:0,他引:4  
A combinatorial data analysis strategy is reviewed that is designed to compare two arbitrary measures of proximity defined between the objects from some set. Based on a particular cross-product definition of correspondence between these two numerically specified notions of proximity (typically represented in the form of matrices), extensions are then pursued to indices of partial association that relate the observed pattern of correspondence between the first two proximity measures to a third. The attendant issues of index normalization and significance testing are discussed; the latter is approached through a simple randomization model implemented either through a Monte Carlo procedure or distributional approximations based on the first three moments. Applications of the original comparison strategy and its extensions to partial association may be developed for a variety of methodological and substantive tasks. Besides rank correlation, we emphasize the topics of spatial autocorrelation for one variable and spatial association between two and mention the connection to the usual randomization approach for one-way analysis-of-variance.  相似文献   
863.
Studied problems of identification, using a meta-contrast design. The first stimulus (A) was always the word ME. In experiment 1 , the second stimulus (B) depicted an aggressor and a victim facing each other. The subliminal A was flashed either on the victim or the aggressor or completely withheld. In experiment 2 , B showed two persons standing against different backgrounds: an open horizon or a closed room. It was assumed that the subject would be "forced" to identify with that figure in B on which A was flashed. Subjects in experiment 1 were 18 psychiatric patients and in experiment 2 , 32 professional artists. The results showed that the subliminal manipulation had been effective: e.g., when led by A to identify with the aggressor, projective-sensitive and borderline subjects were confused and even reported perceptual difficulties; when led to identify with the open side, highly creative artists, as opposed to less creative ones, reported more positive impressions of the B theme.  相似文献   
864.
865.
866.
In Experiment 1 six monkeys were tested with discriminative relations that were backward relative to their training in a 0-second conditional (“symbolic”) matching procedure. Although there was some indication of backward associations, the evidence was generally weak, and statistical evaluations did not reach conventional significance levels. Unlike children, who show backward associations to the point of symmetry, monkeys and pigeons display at best only weak and transient backward associations. In Experiment 2 associative transitivity was assessed across two sets of conditional matching tasks. All four monkeys tested demonstrated strong transitivity. In contrast, in Experiment 3 there was no evidence of transitivity in three pigeons tested under conditions closely comparable to those of Experiment 2. These results may identify some key features of interspecies differences and contribute to analyses of serial learning in animals.  相似文献   
867.
Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.  相似文献   
868.
Correlations (r = 0.50) were found between the numbers of different psi (paranormal) experiences and the numbers of temporal lobe signs within a population of university students (n = 99). The strongest correlation of 0.60 occurred with a cluster of signs that are similar to symptoms reported by patients who show chronic foci in the mesiobasal temporal lobe. However, there were no significant correlations between numbers of different psi experiences and clusters of control items or a lie scale. Specific analyses of the 140 items of the inventory indicated only 23 reached statistical criterion (p less than .001). Of these 17 were direct temporal lobe signs that implied deepened affect, auditory-vestibular experiences (vibrations, hearing one's name called), olfactory auras, perseveration ("forced" thinking), depersonalization, and sense of the personal. Five items involved beliefs about exotic phenomena or philosophical ideas. Only one item was from a control cluster. These results support the hypothesis that mystical or paranormal experiences are associated with transient electrical foci within the temporal lobe of the human brain. The repeated occurrence of these experiences within normal individuals may be embedded within a more complex symptomatology of temporal lobe signs.  相似文献   
869.
On the basis of surveys completed by 105 male participants in a popular marathon, a multiple regression analysis was conducted to identify the variables contributing significantly to the prediction of final time. Overall prediction was successful, with R = .896, and training pace was the most important factor in the equation, speedier workouts being associated with faster marathon times. Final time was also related positively to best 10-km race time in the previous 12 mo. and repression-sensitization (faster runners being more sensitized), and negatively to maximum number of training miles in a single week, number of previous marathons completed, and number of days of training lost through illness or injury. Contrary to expectations, locus of control was not related to final time. Only 27% of the runners had lost training time through injury, but a discriminant analysis showed that, compared to those who had avoided this problem, the injured were younger, rested less, ran less in the week prior to the marathon, ran a slightly longer long run but ran it earlier before the race, and ran fewer runs of 20 miles or more. It is suggested that researchers should study the repression-sensitization variable and investigate injury in runners preparing for a marathon.  相似文献   
870.
The Safety Locus of Control Scale was designed to predict employees' accidents and injuries. Internal scorers think they should assume personal responsibility for their safety, and they believe they can take preventive steps to avoid accidents. External scorers assume little personal responsibility for prevention of accidents. Instead, they place more blame on factors outside their control, such as luck or chance. This study showed that the safety scale was effective in differentiating between groups with varying accident histories, which supports the criterion-related validity of the scale.  相似文献   
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