The greater the magnitude of the item-discrimination index,the more testtakers in the higher-scoring group answered the item correctly,as compared to testtakers
A) who served as the non-test-taking control group.
B) in the lower-scoring group.
C) who participated in the test standardization.
D) None of these

Question

Quizplus · Accepted Answer

The item-discrimination index measures how well an item or question discriminates between testtakers who scored high versus those who scored low. Therefore, a greater magnitude of the item-discrimination index means that more testtakers in the higher-scoring group answered the item correctly than those in the lower-scoring group. So, the correct answer is B - in the lower-scoring group.

The Greater the Magnitude of the Item-Discrimination Index,the More Testtakers