Question

A researcher reports an F-ratio with df = 2, 18 from an independent-measures research study. Based on the df values, how many treatments were compared in the study and what was the total number of subjects participating in the study?​

Answer 1

Answer: 3 treatments and 21 subjects were participating in the study .

Explanation:

Let the number of treatments be k and the total number of subjects participating in the study be n.

Then , the df for numerator of F-ratio = k-1

df for denominator of F-ratio = n-k

Given : A researcher reports an F-ratio with df = 2, 18 from an independent-measures research study.

Based on the df values, we have

k-1 = 2 and n-k= 18

If
`k-1=2\\\Rightarrow\ k=2+1=3`

Then,
`n-3= 18\Rightarrow\ n=18+3=21`

Therefore , 3 treatments were compared in the study and 21 subjects were participating in the study is 21.