The purpose of this article is twofold. The first is to provide evaluative information on the recovery of model parameters and their standard errors for the two-parameter item response theory (IRT) model using different estimation methods by Mplus. The second is to provide easily accessible information for practitioners, instructors, and students…

Reviews a computer-assisted learning package (available from CONDUIT) which includes an introduction to factorial experimental design, and the analysis of the main effects and interactions of two- and three-factor experiments. Indicates that it is a clearly thorough package putting over a limited idea in a very lucid manner. (JN)

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)

This research study reports the results of an attempt to build a model of individual differences in undergraduate student development based on factor analysis of a wide range of students' beliefs and behaviors. An 127-item inventory named the Dakota Inventory of Student Orientations was administered to 738 male and female undergraduate students in…