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…

This study examines the effects of two test administration accommodations on the mathematics performance of students within the context of a large-scale statewide assessment. The two test administration accommodations were resource guides and calculators. A stratified random sample of schools was selected to represent the demographic…

The evidence gathered in the present study supports the use of the simultaneous development of test items for different languages. The simultaneous approach used in the present study involved writing an item in one language (e.g., French) and, before moving to the development of a second item, translating the item into the second language (e.g.,…

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…

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…

Panelists in an operational standard-setting study were asked to share their thoughts in written form at important points in the process itself--before the meeting started, after training, after completing the 1st and 2nd sets of ratings, immediately following the discussion between Rounds 1 and 2, and so on. The item mapping method of Plake and…