Sample homogeneity and coefficient alpha: comment on Mji and Alkhateeb's reliability generalization study and a theoretical clarification

Reliability generalization studies are increasingly frequently reported in the literature, including Mji and Alkhateeb's 2005 study of the Conceptions of Mathematics Questionnaire. The present article comments on an issue of reliability generalization as used in that study and clarifies a theoretical point regarding the meaning of coefficient alpha and what data features tend to influence it as a measure of score reliability.