In achievement testing we assume that students will demonstrate their maximum performance as they encounter test items. Sometimes, however, student performance can decline during a test event, which implies that the test score does not represent maximum performance. This study describes a method for identifying significant performance decline and…

The Student Background survey administered along with achievement tests in studies of the International Association for the Evaluation of Educational Achievement includes scales of student motivation, competence, and attitudes toward mathematics and science. The scales consist of positively- and negatively keyed items. The current research…

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 article used several data sets from a large-scale state testing program to examine the feasibility of combining general and modified assessment items in computerized adaptive testing (CAT) for different groups of students. Results suggested that several of the assumptions made when employing this type of mixed-item CAT may not be met for…

The distinction between quantitative and qualitative differences in mastery is essential when monitoring student progress and is crucial for instructional interventions to deal with learning difficulties. Mixture item response theory (IRT) models can provide a convenient way to make the distinction between quantitative and qualitative differences…

This study examined the validity of test accommodation in third-eighth graders using differential item functioning (DIF) and mixture IRT models. Two data sets were used for these analyses. With the first data set (N = 51,591) we examined whether item type (i.e., story, explanation, straightforward) or item features were associated with item…

Item response theory (IRT) methods are generally used to create score scales for large-scale tests. Research has shown that IRT scales are stable across groups and over time. Most studies have focused on items that are dichotomously scored. Now Rasch and other IRT models are used to create scales for tests that include polytomously scored items.…

A number of vertical scaling methodologies were examined in this article. Scaling variations included data collection design, scaling method, item response theory (IRT) scoring procedure, and proficiency estimation method. Vertical scales were developed for Grade 3 through Grade 8 for 4 content areas and 9 simulated datasets. A total of 11 scaling…