The optimal level of item difficulty is MOST typically
A) .5.
B) the midpoint between 1.0 and the chance of success by random guessing.
C) .25.
D) the midpoint between 0 and the chance of success by random guessing.

Question

Quizplus · Accepted Answer

The optimal level of item difficulty should be located between 1.0 (i.e., extremely difficult) and the chance of success by random guessing (i.e., .5 for a multiple-choice test with four options) in order to provide a sufficient challenge for examinees while still allowing for discrimination among their abilities. The midpoint between these two points is (1.0 + .5)/2 = .75, so the optimal level of item difficulty is close to .75.

The Optimal Level of Item Difficulty Is MOST Typically