Brentari, Eugenio; Golia, Silvia - In: Statistica 67 (2007) 3, pp. 253-261
Unidimensionality, or the fact that the items in a questionnaire measure only a single construct, is a fundamental requirement for the Rasch model. The paper deals with the detection of unidimensionality making use of principal components analysis of residuals and item fit statistics. Simulated...