Dennis asked "how do we know what a test's true reliability is?"
Osburn knew because he simulated true-score covariance matrices and from these obtained observed score covariance matrices as a function of the true-score matrices and hypothetical values of reliability. More details are in his article in Psychological Methods, 2000, 5, 343-355. Karl W. ================================================================= Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =================================================================