Regarding effect size, all of the following statements are true, except:

	1.	Effect sizes are expressed as a standard score, in other words, interpreted in standard deviation units (typically in absolute value terms) from zero.
	2.	Effect size is a measure for expressing the practical importance of the difference between sample means.
	3.	Effect size should be calculated when the pairwise difference is found to be non-significant.
	4.	Effect size is a measure of the magnitude of the significant mean difference.