Guide to calculating, interpreting and using effect size

For example, for an effect-size of 0.6, the value of 73% indicates that the average person in the experimental group would score higher than 73% of a control group that was initially equivalent. If the group consisted of 25 people, this is the same as saying that the average person (i.e. ranked 13th in the group) would now be on a par with the ... ................
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