Increasing the true variance and the observed variance by the same amount will increase the test's
A) arithmetic mean.
B) error variance.
C) reliability.
D) validity.

Question

Quizplus · Accepted Answer

Increasing both the true variance and the observed variance by the same amount does not change the arithmetic mean, error variance, or validity of the test. However, it can increase the reliability of the test, as reliability is a ratio of true variance to observed variance. If both increase by the same amount, the proportion of true variance in the observed variance, which defines reliability, can increase, assuming the increase does not affect the error variance disproportionately.

Increasing the True Variance and the Observed Variance by the Same