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71.
72.
Decompositions and biplots in three-way correspondence analysis 总被引:1,自引:0,他引:1
In this paper correspondence analysis for three-way contingency tables is presented using three-way generalisations of the singular value decomposition. It is shown that in combination with Lancaster's (1951) additive decomposition of interactions in three-way tables, a detailed analysis is possible of the deviations from independence. Finally, biplots are shown to produce powerful graphical representations of the results from three-way correspondence analyses. An example from child development is used to illustrate the theoretical developments. 相似文献
73.
Whereas the unique axes properties of PARAFAC1 have been examined extensively, little is known about uniqueness properties
for the PARAFAC2 model for covariance matrices. This paper is concerned with uniqueness in the rank two case of PARAFAC2.
For this case, Harshman and Lundy have recently shown, subject to mild assumptions, that PARAFAC2 is unique when five (covariance)
matrices are analyzed. In the present paper, this result is sharpened. PARAFAC2 is shown to be usually unique with four matrices.
With three matrices it is not unique unless a certain additional assumption is introduced. If, for instance, the diagonal
matrices of weights are constrained to be non-negative, three matrices are enough to have uniqueness in the rank two case
of PARAFAC2.
The authors are obliged to Richard Harshman for stimulating this research, and to the Associate Editor and reviewers for suggesting
major improvements in the presentation. 相似文献
74.
Maritza Rubio-Stipec Patrick E. Shrout Glorisa Canino Héctor R. Bird Peter Jensen Mina Dulcan Mary Schwab-Stone 《Journal of abnormal child psychology》1996,24(1):67-83
Empirically defined scales of depressive, attention deficit hyperactivity disorder, oppositional-defiant disorder, and conduct symptoms from the lay-administered National Institute of Mental Health (NIMH) Diagnostic Interview Schedule for Children (DISC), version 2.3, and evidence of their reliability and validity, are presented. The scales were developed using factor analyses of data obtained from an epidemiologic survey of over 1,200 children drawn from four sites across the U.S. and Puerto Rico (the NIMH Methods for the Epidemiology of Child and Adolescent Mental Disorders, or MECA Study). Their psychometric properties were tested in a subsample of children reinterviewed by clinicians. The findings support the use of these continuous measures. The scales are strongly related to the diagnostic categories and show good test-retest reliability. The scales can be used to characterize severity in children with diagnoses and to describe problems and symptoms in children without diagnoses. Because these scales can measure gradations in symptomatology, they may be more useful than categorical measures. Like categorical measures, the scales based on the DISC are greatly influenced by the informant, whether child or parent.This research was supported by grant MH-46732 from the National Institute of Mental Health, Bethesda, Maryland.The MECA Program is an epidemiologic methodology study performed by four independent research teams in collaboration with staff of the Division of Clinical Research, which was reorganized in 1992 with components now in the Division of Epidemiology and Services Research and the Division of Clinical and Treatment Research, of the NIMH, Rockville, Maryland. The NIMH Principal Collaborators are Darrel A. Regier, MD, MPH, Ben Z. Locke, MSPH, Peter S. Jensen, MD, William E. Narrow, MD, MPH, and Donald S. Rae, MA; the NIMH Project Officer was William J. Huber. The Principal Investigators and Coinvestigators from the four sites are as follows: Emory University, Atlanta, Georgia, UO1 MH46725: Mina K. Dulcan, MD, Benjamin B. Lahey, PhD, Donna J. Brogan, PhD, Sherryl Goodman, PhD, and Elaine Flagg, PhD; Research Foundation for Mental Hygiene at New York State Psychiatric Institute (Columbia University), New York, New York, UO1 MH46718: Hector R. Bird, MD, David Shaffer, MD, Myrna Weissman, PhD, Patricia Cohen, PhD, Denise Kandel, PhD, Christina Hoven, PhD, Mark Davies, MPH, Madelyn S. Gould, PhD, and Agnes Whitaker, MD; Yale University, New Haven, Connecticut, UO1MH46717: Mary Schwab-Stone, MD, Philip J. Leaf, PhD, Sarah Horwitz, PhD, and Judith H. Lichtman, MPH; University of Puerto Rico, San Juan, Puerto Rico, UO1 MH46732: Glorisa Canino, PhD, Maritza Rubio-Stipec, MA, Milagros Bravo, PhD, Margarita Alegría, PhD, Julio Ribera, PhD, Sarah Huertas, MD, and Michael Woodbury, MD.The authors gratefully acknowledge Zenaida González and José Martínez who performed the data nalayses, as well as Elizabeth Pastrana, and Felícita Laboy, secretaries, for their valuable contributions to this work. 相似文献
75.
Marc Berthiaume Hélène David Jean-François Saucier François Borgeat 《Sex roles》1996,35(11-12):781-800
This study was designed to examine the relationship between gender role orientation and psychological adjustment during pregnancy and the postpartum period in a large sample of French-speaking Caucasian mothers. Gender role was assessed with the Bem Sex Role Inventory, which classifies subjects into four categories: androgynous, masculine, feminine, and undifferentiated. A discriminant analysis showed a relationship between androgyny and the following measures of psychological adaptation: self-esteem, satisfaction with social support, and level of apprehension toward perinatal stressors. The masculine gender role was linked with self-esteem, work involvement, age, and severity of perinatal stress. No relationship was found between gender role and the level of antenatal or postnatal depressive symptomatology. Stress, marital support, and social support were among the predictors of postpartum depression, which underlined the importance of taking these variables into account when studying the well-being of mothers during the postnatal period. Results are discussed in light of previous literature on the association between gender role and motherhood. The limitations of Bem's model and inventory are also considered. 相似文献
76.
Will A. C. Spijkers Petra Wallmeyer Jos J. Adam Fred G. W. C. Paas Martinus J. Buekers Irina J. Wuyts 《Psychological research》1996,59(2):107-118
Two experiments are reported in which, by means of a pointing task, we studied the stimulus-position effect, i.e. the inverted U-shape form of the reaction-time function in relation to stimulus position in tasks in which stimuli and/or responses are arranged in a horizontal array. The response consisted of aiming the index finger from a central starting point at a target area on a screen. Reaction time was the main dependent variable. The spatial relation between the position of the imperative signal and the position of the response was manipulated by varying the spatial S-R compatibility and physical distance that separated the positions of stimulus and response. The stimulus-position effect was shown to depend on the compatibility of the S-R relation (Exp. 1). In Exp. 2 it was found that the modulation of the stimulus-position effect by spatial compatibility disappeared completely when the distance between the positions of stimulus and response was reduced. None of the experiments revealed that the stimulus position effect depended on signal discriminability, which renders an interpretation of this effect in terms of perceptual processes unlikely. We argue that the attentional model of spatial coding provides the most reasonable explanation of the obtained reaction-time patterns. 相似文献
77.
78.
This article presents an approach we have developed for the assessment of public research institutions in the natural sciences
and engineering. The method consists in the exploitation of available S&T databases and indicators, including bibliometrics
(databases of scientific as well as technical literature), patents, and internal data. Results are therefore derived through
multiple databases. The objective is to profile a specific national R&D community in order to assess the positioning of a
public institution or program within the community to which it belongs. It involves obtaining the profile of the evolution
of an R&D area, the R&D performers, the financing and support institutions, the users of R&D results, and the interactions
between all these actors. A case-study of Canadian research in polymers is presented.
Part of this research was financed by the National Research Council of Canada, and by a strategic grant from the Social Sciences
and Humanities Research Council. The research benefited from the expertise of Robert Letellier, Robert H. Marchessault, Jacques
Martel, and Marielle Piché, and from the technical assistance of Maryse Prud’homme, Marcel Parent, and Benoit Longpré. 相似文献
79.
Steven A. Meyers PhD Gary E. Stollak PhD Joel Aronoff PhD Lawrence A. Messé PhD John A. Loraas MA Barbara A. Woike PhD 《Contemporary Family Therapy》1996,18(2):279-290
Examination of boundary regulation can provide family therapists with a framework to describe both the functioning of family systems and personal systems (i.e., the intrapsychic functioning of individual family members). In the present study, late adolescents' perceptions of boundary regulation within their family systems (i.e., ratings of family health, communication, leadership, expressiveness, cohesion, and family conflict) were related to regulation of their personal boundaries (i.e., self-reported personal competence, distress, and patterns of defense mechanism use). In addition, personal system variables reliably discriminated between adolescents who described their families as psychologically healthy versus psychologically unhealthy. 相似文献
80.