In an item analysis, 10 students each in the upper and the lower groups attempted an item. Eight students in the upper group and three in the lower group answered it correctly. What are the discrimination index and the difficulty index of the item?
- A0.50 and 0.55
- B0.50 and 0.45
- C0.55 and 0.50
- D0.25 and 0.55
Correct answer: A