A treatment is administered to a sample of n = 9 individuals selected from a population with a mean of µ = 80 and a standard deviation of σ = 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?
A)M = 6
B)M = 82
C)M = 86
D)This cannot be answered without knowing the sample size.

Question

A treatment is administered to a sample of n = 9 individuals selected from a population with a mean of µ = 80 and a standard deviation of σ = 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?​
A)​M = 6
B)​M = 82
C)​M = 86
D)​This cannot be answered without knowing the sample size.

Quizplus · Accepted Answer

Cohen's d measures the standardized difference between two means. A value of d = 0.50 indicates a moderate effect size. To calculate the mean for the treated sample, we can use the formula:

d = (M - µ) / σ

Where M is the mean for the treated sample, µ is the population mean, and σ is the population standard deviation.

Substituting the given values, we get:

0.50 = (M - 80) / 12

Solving for M:

M - 80 = 0.50 * 12
M - 80 = 6
M = 86

Therefore, the mean for the treated sample is M = 86. The correct answer is C.

A Treatment Is Administered to a Sample of N =