Question

The data from an independent-measures research study produce a sample mean difference of 4 points and a pooled variance of 18. If there are n = 4 scores in each sample, what is the estimated standard error for the sample mean difference?​

Answer 1

Answer: 3

Explanation:

Given : Pooled variance :
`\sigma^2=18`

Sample sizes of each sample =
`n_1=n_2=4`

We know that the standard error for the sample mean difference is given by :-

`S.E.=\sqrt{\sigma^2((1)/(n_1)+(1)/(n_2))}\\\\=\sqrt{(18)((1)/(4)+(1)/(4))}\\\\=\sqrt{(18)((1)/(2))}=√(9)=3`

Hence, the estimated standard error for the sample mean difference =3