The definition of reliability as the ratio of true score variable to observed score variance comes from
A) dependability theory.
B) classical test theory.
C) generalizability theory.
D) item response theory.

Question

Quizplus · Accepted Answer

This definition of reliability comes from classical test theory, which posits that each observed score is the sum of a true score and an error score. The reliability is thus conceptualized as the proportion of variance in observed scores that is due to true scores.

The Definition of Reliability as the Ratio of True Score