Conceptualizing two-variable disturbances preventing good model fit in confirmatory factor analysis as item-level method effects instead of correlated residuals avoids violating the principle that residual variation is unique for each item. The possibility of representing such a disturbance by a method factor of a bifactor measurement model was…

The main purpose of this paper is to investigate the intellectual structure of the research on educational technology in science education (ETiSE) within the most recent years (2008-2013). Based on the criteria for educational technology research and the citation threshold for educational co-citation analysis, a total of 137 relevant ETiSE papers…

Considers P. Schonemann's simulation study in light of the multigroup principal component analysis model and interprets it as a study of the specificity of Spearman correlations, given model violations. Asserts that the Spearman correlation is a suboptimal test of Spearman's hypothesis and contends that an explicit model-based approach should be…

Fifty-five recent studies of individual differences (IDs) in elementary cognitive tasks (ECTs) are reviewed. Twenty-five data sets are examined, analyzed, or reanalyzed by factor analysis. The following promising dimensions are identified: basic perceptual processes, reaction and movement times, mental comparison and recognition tasks, retrieval…