The amount of difference that exists among the populations with unknown means (which you have sampled from) is the issue of
A) hypothesis testing or confidence intervals
B) assumptions of ANOVA
C) .05 or .01 $\alpha$ level
D) effect size.

Question

Quizplus · Accepted Answer

Effect size is a quantitative measure of the magnitude of the experimenter effect. It specifically addresses the amount of difference among populations, beyond just the significance of this difference, which is what hypothesis testing or determining confidence intervals would do.

The Amount of Difference That Exists Among the Populations with Unknown