Although content validity--how well each item of an instrument represents the construct being measured--is foundational in the development of an instrument, statistical validity is also important to the decisions that are made based on the instrument. The primary purpose of this study is to demonstrate how simulation studies can be used to assist…

A computer simulation procedure was developed to reproduce the overall pattern of results obtained in the Educational Testing Service Growth Study. Then simulated data for seven sets of 10,000 to 15,000 cases were analyzed, and findings compared on the basis of correlations between estimated and true growth scores. Findings showed that growth was…

Development of The Assessment of Basic Competencies (ABC), a test battery based on the three-parameter logistic model, is described. Eleven dimensions of intellectual growth are measured, from the pre-kindergarten level through ninth grade. An educationally relevant skill domain is represented by each test. Unique properties of the test, based on…