Which statement is TRUE regarding an item-discrimination index?
A) It has been used by e-Harmony.com and other dating sites for matchmaking.
B) There is more than one formula for calculating an item-discrimination index.
C) Tetrachoric correlation is most frequently used in any formula for an item-discrimination index.
D) All of these.

Question

Quizplus · Accepted Answer

There are multiple formulas for calculating an item-discrimination index, including point-biserial correlation and phi coefficient. Option A is not true as an item-discrimination index is not used by dating sites. Option C is incorrect as tetrachoric correlation is only used in certain situations, such as when dealing with dichotomous variables.

Which Statement Is TRUE Regarding an Item-Discrimination Index