Initial Progress Rates as Related to Performance in a Personalized System of Instruction

Allen G. J. Giat L. Cherney R. J. Locus of control, test anxiety, and student performance in a personalized instruction course. Journal of Educational Psychology, 1974, 6, 968–973.

Wilson S . A useful statistic: The G statistic as a measure of behavior change. San Rafael: Individual Learning Systems Corporation, 1971.