This comprehensive "Handbook" focuses on the most used polytomous item response theory (IRT) models. These models help us understand the interaction between examinees and test questions where the questions have various response categories. The book reviews all of the major models and includes discussions about how and where the models…

Discusses the complicating effects of ambivalence on the validity of science attitude measurement scales. Cites studies indicating that the positive and negative effects about a particular psychological object are not necessarily bipolar. Suggests the use of factor analysis to check dimensionality in instruments. (TW)