When we calculate reliability, we know the observed score. What are the two unknown components of the reliability equation?
A) Method and error scores
B) Means and standard deviations
C) Test-retest and interrater scores
D) True and error scores

Question

Quizplus · Accepted Answer

The two unknown components of the reliability equation are the true score (the score that represents a person's actual ability or trait) and the error score (the amount by which the observed score deviates from the true score due to measurement error). Option D correctly identifies the true and error scores as the two unknown components. Option A is incorrect because method refers to the specific measurement tool or technique used, which is not an unknown component in reliability calculation. Option B is incorrect because means and standard deviations are descriptive statistics used to summarize data, and are not components of the reliability equation. Option C is incorrect as it refers to different types of reliability rather than the unknown components of the reliability equation.

When We Calculate Reliability, We Know the Observed Score