Question

A treatment is administered to a sample of n = 9 individuals selected from a population with a mean of m = 80 and a standard deviation of s = 12. after treatment, the effect size is measured by computing cohen's d, and a value of d = 0.50 is obtained. based on this information, what is the mean for the treated sample?

Answer 1

Cohen's d is calculated according to the formula:
d = (mean difference) / standard deviation
0.5 = mean difference / 12
Therefore, mean difference = 6
Since we have a population mean of 80, the sample mean must be 80 + 6 = 86.