According to classical test theory, if the observed variance of a test is 50 and the true variance is 40, what is the estimated reliability of the test
The ratio of true score variance to the observed score variance: 40/50 = 0.80
To estimate the reliability of a test using classical test theory, you can use the formula:
Reliability = (True Variance) / (Observed Variance)
In this case, the observed variance is 50 and the true variance is 40.
Reliability = 40 / 50
Reliability = 0.8
Therefore, the estimated reliability of the test is 0.8 or 80%.