A. Item difficulty is near zero
B. Item difficulty is near 100
C. Item difficulty is near 70
D. Item difficulty is near 50
Answer is = D
In a norm-referenced test, the ideal item difficulty is closest to:
D. Item difficulty is near 50
Here’s why:
- Norm-referenced tests (NRTs) are designed to compare students’ performances against each other. They aim to spread out the scores so that a wider range of student abilities can be effectively distinguished.
- Items with difficulty near 0 (very easy): If most students answer an item correctly, it doesn’t effectively differentiate between high and low performers. These items wouldn’t be very useful for gauging a wide range of abilities in a norm-referenced test.
- Items with difficulty near 100 (very difficult): If most students struggle with an item, it again doesn’t provide much information for differentiating student performance.
Items with difficulty near 50 are considered ideal for norm-referenced tests because:
- They allow some students to demonstrate mastery by answering correctly, while still challenging others.
- They provide a good opportunity to discriminate between students with different levels of knowledge or skill.
This doesn’t mean all items in a norm-referenced test should have exactly 50% difficulty. There can be a range of difficulty levels, but having a good proportion of items around the 50% mark helps ensure the test effectively spreads out scores and differentiates student performance.