ERIC Number: EJ633927
Record Type: Journal
Publication Date: 2001
Reference Count: N/A
Statistical Power for Nonequivalent Pretest-Posttest Designs: The Impact of Change-Score versus ANCOVA Models.
Oakes, J. Michael; Feldman, Henry A.
Evaluation Review, v25 n1 p3-28 Feb 2001
Describes and compares useful and unified power formulas for analysis of covariance and change-score analyses, indicating the implications of each for sample size requirements. Contains practical recommendations for evaluations and outlines a simple spreadsheet approach. (SLD)
Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Authoring Institution: N/A
IES Cited: ED503448