A measure is perfectly reliable if ________.
A) XS = 0
B) XT = 0
C) XO = 0
D) XR = 0

Question

Quizplus · Accepted Answer

Perfect reliability is achieved when there is no variability in measurement over time, and this is indicated by a perfect test-retest correlation (r = 1) and a standard error of measurement (SEM) of 0. The symbol used to represent standard error of measurement is SEM and for test-retest reliability is XR. Therefore, if XR = 0, it indicates that the measure is perfectly reliable.

A Measure Is Perfectly Reliable If ________