Factor analysis is a statistical method to explore the relationships among observed variables and identify latent structures. It is crucial in scale development and validity analysis. Key factors affecting the accuracy of factor analysis results include the type of data, sample size, and the number of response categories. While some studies…

This report summarizes some of the evidence supporting interpretations of scores from the enhanced ACT, focusing on reliability, concurrent validity, predictive validity, and score comparability. The authors argue that the evidence presented in this report supports the interpretation of scores from the enhanced ACT as measures of high school…

This study investigates the impact of violating the local item independence assumption by loading certain items onto a second dimension on test equating errors in unidimensional and dichotomous tests. The research was designed as a simulation study, using data generated based on the PISA 2018 mathematics exam. Analyses were conducted under 36…