This report provides a description of the development process, field testing, and psychometric properties of a student mathematics test designed to assess grades K, 1, and 2 student abilities. The test was administered to 4,486 participating grade K, 1, and 2 students in 67 schools located in 10 public school districts in Florida during fall 2015.…

This report provides a description of the development process, field testing, and psychometric properties of a student mathematics test designed to assess grades 1 and 2 student abilities. The test was administered to 2,373 participating grade 1 and 2 students in 22 schools located in 2 public school districts in Florida during fall 2013. Focused…

This study examines the use of cross-classified random effects models (CCrem) and cross-classified multiple membership random effects models (CCMMrem) to model rater bias and estimate teacher effectiveness. Effect estimates are compared using CTT versus item response theory (IRT) scaling methods and three models (i.e., conventional multilevel…

This study examines model selection indices for use with dichotomous mixture item response theory (IRT) models. Five indices are considered: Akaike's information coefficient (AIC), Bayesian information coefficient (BIC), deviance information coefficient (DIC), pseudo-Bayes factor (PsBF), and posterior predictive model checks (PPMC). The five…