List of Titles

Authors: De Bruin, G.P.
Date: 2004
Subjects: Factor analysis , Unidimensional scales , Non-linear relations , Rasch rating scale model , Locus of control inventory
Type: Article
Identifier: uj:6570 , http://hdl.handle.net/10210/2870
Description: The factor analysis of items often produces spurious results in the sense that unidimensional scales appear multi-dimensional. This may be ascribed to failure in meeting the assumptions of linearity and normality on which factor analysis is based. Item response theory is explicitly designed for the modelling of the non-linear relations between ordinal variables and provides a strong alternative to the factor analysis of items. Items may also be combined in parcels that are more likely to satisfy the assumptions of factor analysis than do the items. The use of the Rasch rating scale model and the factor analysis of parcels is illustrated with data obtained with the Locus of Control Inventory. The results of these analyses are compared with the results obtained through the factor analysis of items. It is shown that the Rasch rating scale model and the factoring of parcels produce superior results to the factor analysis of items. Recommendations for the analysis of scales are made.
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Authors: De Bruin, G.P. , Swartz, L. , Tomlinson, M. , Cooper, P. , Molteno, C.
Date: 2004
Subjects: Edinburgh postnatal depression scale , EPDS , Factor analysis
Type: Article
Identifier: uj:6571 , http://hdl.handle.net/10210/2871
Description: The factor structure of the Edinburgh Postnatal Depression scale (EPDS) and similar instruments have received little attention in the literature. The researchers set out to investigate the construct validity and reliability of the EPDS amongst impoverished South African women. The EPDS was translated into isiXhosa (using Brislin’s back translation method)and administered by trained interviewers to 147 women in Khayelitsha, South Africa. Responses were subjected to maximum likelihood confirmatory factor analysis. A single factor structure was found, consistent with the theory on which the EPDS was based. Internal consistency was satisfactory (a = 0.89).
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Authors: Vorster, Paul Petrus
Date: 2012-06-06
Subjects: Psychometrics , Psychiatric rating scales , Factor analysis , Factorial experiment designs
Type: Mini-Dissertation
Identifier: uj:2487 , http://hdl.handle.net/10210/4941
Description: M.Comm. , It was investigated whether dichotomous (2-point) or polytomous (5-point) rating scales have superior functioning on the personality construct Soft-Heartedness for the South African Personality Inventory (SAPI). The optimal number of rating scale categories for a personality measure was explored. The participants comprised students of diverse racial and cultural backgrounds at a South African tertiary institution (N =708). Two alternate forms of a test measuring Soft-Heartedness were administered to two alternated groups (n1 = 344; n2 = 364). Either version of the test contained a 2-point and 5-point version. These two formats were then factor analysed and subjected to a tetrachoric/polychoric correlation analysis. They were also tested for reliability using the Cronbach Alpha coefficient and composite reliability coefficient. In addition, the coefficient of congruence was established. It was found that the 2-point scale has more functional psychometric properties than the 5-point scale regarding the factor structure and composite reliability. This was attributed to cultural, perceptual, linguistic, educational, and test-experience components.
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Authors: De Bruin, G.P.
Date: 2006
Subjects: General work stress , Factor analysis , Work stress scale
Type: Article
Identifier: uj:6564 , http://hdl.handle.net/10210/2864
Description: This study examined the dimensionality or factor structure of the General Work Stress Scale (GWSS), which is a brief measure of subjectively experienced or felt work stress. The responses of two independent groups of adult workers were subjected to maximum likelihood factor analysis. In both groups a three factor solution provided the best fit with the data. A higher order factor analysis with an orthogonal Schmid-Leiman transformation showed that in both groups, responses to the items are dominated by a general factor, which might be labelled General Work Stress. Three minor group factors were identified: a motivational factor reflected by a desire to leave the organisation, an affective factor reflected by a tendency to worry, and a cognitive factor reflected by concentration and attentional difficulties. Overall, the results provide support for the construct validity of the GWSS as a measure of subjectively experienced work stress.
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