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 2
Choose the method of estimating score reliability that would be most useful for each of the types of tests listed below. An achievement test to be given as a pretest and a posttest in a classroom research study
a. equivalent forms c. test-retest
b. split-half