Factor analysis for items or testlets scored in more than two categories

Citation

Swygert, K.A., Mcleod, L.D., & Thissen, D. (2001). Factor analysis for items or testlets scored in more than two categories. In Thissen, D. & Wainer, H. (Eds.), Test Scoring (pp. 217-250). Mahwah, NJ: Lawrence Erlbaum Associates.

Abstract