One fundamental assumption of item response theory is that each item is constructed so that it measures only one trait or ability. This assumption is known as:
A)the one-trait assumption.
B)single ability measurement.
C)unitary attribute theory.
D)unidimensionality.

Question

Quizplus · Accepted Answer

The assumption that each item measures only one trait or ability in item response theory is known as unidimensionality. This concept is crucial for ensuring that the analysis accurately reflects the ability or trait being measured without the interference of other factors.

One Fundamental Assumption of Item Response Theory Is That Each