ERIC Number: ED403297
Record Type: Non-Journal
Publication Date: 1996-Jun
Reference Count: N/A
An Empirical Investigation of the Accuracy of a Step-Up Method for Estimating Test Score Conditional Variances.
Go, Imelda C.; Woodruff, David J.
In previous works, D. J. Woodruff derived expressions for three different conditional test score variances: (1) the conditional standard error of prediction (CSEP); (2) the conditional standard error of measurement in prediction (CSEMP); and (3) the conditional standard error of estimation (CSEE). He also presented step-up formulas that require only weak assumptions and allow the estimation of full-length test score conditional variances from two parallel half-length tests. This study empirically investigates the accuracy of the step-up formulas using real test data from 40,000 examinees with scores on the ACT Assessment and concludes that the step-up formulas work fairly well for the CSEP and the CSEMP and less well for the CSEE. The CSEMP is also compared with two other procedures for estimating the conditional standard error of measurement. Appendixes present derivations and study the figures. (Contains two tables, eight appendix figures, and eight references.) (Author/SLD)
Descriptors: College Entrance Examinations, Error of Measurement, Estimation (Mathematics), High School Students, High Schools, Prediction, Scores, Test Items
ACT Research Report Series, P.O. Box 168, Iowa City, IA 52243-0168.
Publication Type: Reports - Evaluative
Education Level: N/A
Authoring Institution: American Coll. Testing Program, Iowa City, IA.
Identifiers - Assessments and Surveys: ACT Assessment