One way ANOVA - calculate degrees of freedom error

Question

There are 6 participants tested with differnt 6 medicines with enought time between. Medicine is factor in the one way anova. The formulae given to me was n-i*j. I tried to plug it in several times, but none showed the answer I was given to help me. I got the answer from formulae of (n-1)-(i-1)-(j-1) = (36-1) - (5-1)- (1-1) = 30 . However, I do not see it from the n-i*j formulae.

Thank you

Answer 1

Hi,

The degrees of freedom formula for this deign is (n-1)*j, where n= # of subjects in each group, j=# of groups.

So in this study, n=6, j=6, so the error degrees of freedom is (6-1)*6=30.