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921.
The fuzzy perspective in statistical analysis is first illustrated with reference to the “Informational Paradigm” allowing us to deal with different types of uncertainties related to the various informational ingredients (data, model, assumptions). The fuzzy empirical data are then introduced, referring to J LR fuzzy variables as observed on I observation units. Each observation is characterized by its center and its left and right spreads (LR1 fuzzy number) or by its left and right “centers” and its left and right spreads (LR2 fuzzy number). Two types of component models for LR1 and LR2 fuzzy data are proposed. The estimation of the parameters of these models is based on a Least Squares approach, exploiting an appropriately introduced distance measure for fuzzy data. A simulation study is carried out in order to assess the efficacy of the suggested models as compared with traditional Principal Component Analysis on the centers and with existing methods for fuzzy and interval valued data. An application to real fuzzy data is finally performed. We would like to express our gratitude to the Editor, the Associate Editor, and the Referees whose comments and suggestions improved significantly the quality of the paper.  相似文献   
922.
This study describes the development and evaluation of a multi-item scale for analyzing the genetic counseling process, the Manchester Observation Code (MOC) for genetic counseling. The instrument is specific to the field of genetic counseling and is designed for analysis of the communication between counselor and client. Coding is done directly from videotaped sessions. Because communication is the means by which genetic counseling is accomplished, the method measures four relevant components of communication: (1) grammatical form, (2) purpose, (3) subject, and (4) cue source. The instrument enables an observer to code the counselor's statements into these four components. Three videotaped sessions were used to measure interrater reliability, or the consistency of rating for each of the four communication domains using this method. Three videotaped sessions were also used to measure test-retest reliability, or the consistency of the designed method from one time to another. A total of 21 videotaped sessions were tested using the method. A statistical measure of reliability established consistency of the designed method; Cohen's kappa yielded 0.7 for interrater reliability and 0.79 for test-retest reliability. These findings suggest this instrument may be used to identify important elements of the genetic counseling process.  相似文献   
923.
Dimensions of fatigue in different working populations   总被引:2,自引:0,他引:2  
Perceived fatigue related to work has often been measured in one dimension. The main purpose of the present study was to validate a proposed five-factor model of perceived fatigue in a new sample. 597 persons, employed in five occupations with different types of work loads, rated their fatigue after work. The ratings were subjected to analyses of linear structural equation models. The results suggest a slightly revised model for perceived fatigue, still with the five dimensions: Lack of energy, Physical exertion, Physical discomfort, Lack of motivation and Sleepiness. As expected, the rating profiles describing fatigue states differed between the five occupations. On the basis of these results, a revised version of the Swedish Occupational Fatigue Inventory (SOFI) is presented.  相似文献   
924.
An alternating least squares method for iteratively fitting the longitudinal reduced-rank regression model is proposed. The method uses ordinary least squares and majorization substeps to estimate the unknown parameters in the system and measurement equations of the model. In an example with cross-sectional data, it is shown how the results conform closely to results from eigenanalysis. Optimal scaling of nominal and ordinal variables is added in a third substep, and illustrated with two examples involving cross-sectional and longitudinal data.Financial support by the Institute for Traffic Safety Research (SWOV) in Leidschendam, The Netherlands is gratefully acknowledged.  相似文献   
925.
The choice of constraints in correspondence analysis   总被引:2,自引:0,他引:2  
A discussion of alternative constraint systems has been lacking in the literature on correspondence analysis and related techniques. This paper reiterates earlier results that an explicit choice of constraints has to be made which can have important effects on the resulting scores. The paper also presents new results on dealing with missing data and probabilistic category assignment.I am most grateful to the following for their helpful comments. Arto Demirjian, Michael Greenacre, Michael Healy, Shizuhiko Nishisato, Roderick Mcdonald, and several anonymous referees.  相似文献   
926.
We report an investigation of 9-year-olds' ability to interpret idioms in relation to their reading comprehension level. We manipulated whether the idioms were transparent or opaque, whether they were real or novel, whether they were presented in isolation or in a supportive narrative context. As predicted, children were better able to explain the meanings of idioms in context than in isolation. The good and poor comprehenders did not differ in their abilities to interpret transparent idioms in context, but the poor comprehenders were significantly worse at using context to work out the meanings of opaque idioms. The explanation task revealed the source of information used by the children to derive nontarget interpretations. We discuss these findings in relation to idiom processing strategies and Levorato and Cacciari's global elaboration model.  相似文献   
927.
The educators’ work in juvenile justice residential communities and their capacity of affective attunement to the adolescent's needs is essential for the creation of a protective and enriching context for the adolescent and his life trajectories. This article aims to explore the social representations of educators and young people in residential communities in Italy, through the analysis of their discourses gathered during focus groups. Our results reveal the need to compare these representations and work to narrow the gap between the caregivers and the users, in order to improve the relationship between the different protagonists of the interaction and, consequently, the possibilities of good success of interventions.  相似文献   
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