The Cattell-Horn-Carroll (CHC) taxonomy of cognitive abilities married John Horn and Raymond Cattell's Extended Gf-Gc theory with John Carroll's Three-Stratum Theory. While there are some similarities in arrangements or classifications of tasks (observed variables) within similar broad or narrow dimensions, other salient theoretical features 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…

The articles in this special issue make two important contributions to our understanding of the impact of accommodations on test score validity. First, they illustrate a variety of methods for collection and rigorous analyses of empirical data that can supplant expert judgment of the impact of accommodations. These methods range from internal…

This study compared the underlying factors measured by a state standards-based grade 4 English-Language Arts (ELA) assessment given to several groups of students. The focus of the research was to gather evidence regarding whether or not the tests measured the same construct or constructs for students without disabilities who took the test under…

This study examined the extent to which the underlying factor structure of the 2005 South Carolina Palmetto Achievement Challenge Tests (PACT) in science for grades 3, 4, and 5 was equivalent for students who were administered the test in a regular (standard) or accommodated form. Three accommodation groups were of interest: students who received…