Normal theory maximum likelihood (ML) is by far the most popular estimation and testing method used in structural equation modeling (SEM), and it is the default in most SEM programs. Even though this approach assumes multivariate normality of the data, its use can be justified on the grounds that it is fairly robust to the violations of the…

Exploratory factor analysis (EFA) is a frequently used multivariate analysis technique in statistics. Jennrich and Sampson (1966) solved a significant EFA factor loading matrix rotation problem by deriving the direct Quartimin rotation. Jennrich was also the first to develop standard errors for rotated solutions, although these have still not made…

The Raven Advanced Progressive Matrices Test (APM) is a well-known measure of higher order general mental ability. The time to administer the test, 40 to 60 minutes, is sometimes regarded as a drawback. To meet efficiency needs, the APM can be administered as a 30-or 40-minute timed test, or one of two developed short versions could be used. In…

The Matrices and Order of Appearance subtests of a Piagetian test battery were administered to a sample of second-grade children on two occasions under two test conditions: standardized testing and a dialogue between child and examiner. Differences for test condition and time of testing were found. (JKS)