Multivariate count data is ubiquitous in many areas of research including the physical, biological, and social sciences. These data are traditionally modeled with the Dirichlet Multinomial distribution (DM). A new, more flexible Dirichlet-Tree Multinomial (DTM) model is gaining in popularity. Here, we consider Bayesian DTM regression models. Our…

Multiple group modeling is one of the methods to address the measurement noninvariance issue. Traditional studies on multiple group modeling have mainly focused on item responses. In computer-based assessments, joint modeling of response times and action counts with item responses helps estimate the latent speed and action levels in addition to…

This large-scale, longitudinal study examines teacher attrition data from over 6,500 teachers in Illinois over a 14-year period from 1997 to 2010. Attrition rates between teachers who participated in a Professional Development School (PDS) versus students prepared traditionally are compared. The effects of teacher preparation experiences on…

In 2 experiments the authors investigated whether assigning a perspective to middle school students prior to reading a long informational text would improve their reading comprehension. Pretest-posttest control group designs were employed in both experiments, in Experiment 1 (n = 146 fifth- and sixth-grade students) and in Experiment 2 (n = 83…

Three different versions of a learning program on trigonometry were compared, a program controlled, non-interactive version (CG), an interactive, conflict inducing version (EG 1), and an interactive one which was supposed to reduce the occurrence of a cognitive conflict regarding the central problem solution (EG 2). Pupils (N = 101) of a…