The Kuder-Richardson 21 formula for estimating the score reliability of a classroom achievement test has the disadvantage that
A) it is difficult to compute.
B) it assumes that all test items are of equal difficulty.
C) it is inappropriate for a power test.
D) the resulting reliability coefficient must be adjusted by using another formula.

Question

Quizplus · Accepted Answer

The Kuder-Richardson 21 formula assumes that all test items are of equal difficulty, which is a disadvantage as it may not accurately reflect the actual difficulty level of the items.

The Kuder-Richardson 21 Formula for Estimating the Score Reliability of a Classroom