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91.
This paper presents an analysis, based on simulation, of the stability of principal components. Stability is measured by the expectation of the absolute inner product of the sample principal component with the corresponding population component. A multiple regression model to predict stability is devised, calibrated, and tested using simulated Normal data. Results show that the model can provide useful predictions of individual principal component stability when working with correlation matrices. Further, the predictive validity of the model is tested against data simulated from three non-Normal distributions. The model predicted very well even when the data departed from normality, thus giving robustness to the proposed measure. Used in conjunction with other existing rules this measure will help the user in determining interpretability of principal components.The authors would like to thank the four anonymous reviewers and the two editors for their valuable comments. Atanu R. Sinha gratefully acknowledges the research support received from the Marketing Studies Center, AGSM, UCLA. Send requests for reprints to Atanu R. Sinha, B418 Gold Hall, 110 Westwood Plaza, Los Angeles, CA 90095. 相似文献
92.
Shi-Xu 《Argumentation》1995,9(2):371-398
Traditionally, attitudes are supposed to predict behavior. However, due to their poor performance, we are sometimes advised to abandon the notion. The present study attempts to preserve the concept but takes attitudes to be evaluative goals accomplished through interactional, especially argumentative and explanatory activities. The paper uses reasoned-discourse analysis and demonstrates the attainment of positive attitudes towards the Dutch by expatriate Chinese intellectuals in the Netherlands by attending to a variety of argumentative and explanatory strategies in their interview talk. Results suggest that there is good empirical reason to believe that attitudes are accomplishments of communicating actors' rhetorical contextualizations. 相似文献
93.
Thomas G. Haring Ph.D. 《Journal of Behavioral Education》1995,5(2):123-149
This paper presents a behavioral model which proposes that operants are organized and regulated into systems of responding. Multi-operant theory proposes that operants are organized into response systems that interact to adapt behavior to the complexities of the environment. The operant is the interaction between behavior and the environment which includes the conditions under which responses may occur, the class of behavior that is likely to be effective in producing outcomes, and the antecedent conditions that define the context of behavior. A central feature of this theory is that operants within a repertoire are organized into regulated systems of responding. The mechanisms of regulation are themselves operants that are learned and controlled by processes that are the same as those that govern more overt behavior. Operants stand in relationship to each other in coordinated response systems with some operants directly affecting and organizing the performance of other operants. An important implication of the systemic nature of behavioral repertoires is that bringing some aspect of a behavior class under control of new variables may demonstrate a spread throughout the entire operant system depending on past histories linking the classes.deceased 相似文献
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Comparative evaluation of two superior stopping rules for hierarchical cluster analysis 总被引:1,自引:0,他引:1
A split-sample replication stopping rule for hierarchical cluster analysis is compared with the internal criterion previously found superior by Milligan and Cooper (1985) in their comparison of 30 different procedures. The number and extent of overlap of the latent population distributions was systematically varied in the present evaluation of stopping-rule validity. Equal and unequal population base rates were also considered. Both stopping rules correctly identified the actual number of populations when there was essentially no overlap and clusters occupied visually distinct regions of the measurement space. The replication criterion, which is evaluated by clustering of cluster means from preliminary analyses that are accomplished on random partitions of an original data set, was superior as the degree of overlap in population distributions increased. Neither method performed adequately when overlap obliterated visually discernible density nodes.This research was supported in part by NIMH grant 5R01 MH 32457 14. 相似文献
100.
Kevin J. Miller Barbara S. McCrady David B. Abrams Erich W. Labouvie 《Journal of psychopathology and behavioral assessment》1994,16(2):111-120
The present study reports on a clinical instrument designed for assessing self-efficacy in alcoholics. In contrast to studies that construct general measures, it was proposed that taking an individualized approach to assessment might offer an effective methodology. Thirty-four alcoholics in an outpatient, behaviorally oriented treatment program participated as subjects. During therapy, an Individualized Self-Efficacy Survey (ISS) was developed for each subject. The ISS was developed by (a) administering the Drinking Patterns Questionnaire (DPQ) to identify important problem areas (e.g., work, children, marital) and specific drinking antecedents and (b) constructing a 15-item scale using each drinker's most important cues. The utility of having clients choose their own items was supported by finding a significant relationship between problem areas identified as important on the DPQ and the areas reported as surrounding relapse. ISS ratings were reflective of efficacy changes during treatment, while posttreatment ISS scores were predictive of subsequent relapse. Situation-specific prediction of relapse was not found. The advantages of this methodology for clinical use are discussed, while general directions for future research are suggested. 相似文献