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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
935.
Combinatorial data analysis: Association and partial association 总被引:4,自引:0,他引:4
Lawrence J. Hubert 《Psychometrika》1985,50(4):449-467
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
936.
GUDMUND J. W. SMITH INGEGERD CARLSSON ANNA DANIELSSON 《Scandinavian journal of psychology》1985,26(1):74-87
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
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Effects of ratio reinforcement schedules on discrimination performance by Japanese monkeys
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Fujita K 《Journal of the experimental analysis of behavior》1985,43(2):225-234
In Experiment 1, Japanese monkeys were trained on three conditional position-discrimination problems with colors as the conditional cues. Within each session, each problem was presented for two blocks of ten reinforcements; correct responses were reinforced under continuous-reinforcement, fixed-ratio 5, and variable-ratio 5 schedules, each assigned to one of the three problems. The assignment of schedules to problems was rotated a total of three times (15 sessions per assignment) after 30 sessions of acquisition training. Accuracy of discrimination increased to a moderate level with fewer trials under CRF than under ratio schedules. In contrast, the two ratio schedules, fixed and variable, were more effective in maintaining accurate discrimination than was CRF. With further training, as asymptotes were reached, accuracy was less affected by the schedule differences. These results demonstrated an interaction between the effects of reinforcement schedules and the level of acquisition. In Experiment 2, ratio sizes were gradually increased to 30. Discrimination accuracy was maintained until the ratio reached 20; ratio 30 strained the performance. Under FR conditions, accuracy increased as correct choice responses cumulated after reinforcement. 相似文献