Hello,
This is regarding my previous question.I have now modeled the design
matrix using flexible factorial, with four factors - subject, group, C1 and
C2.Since I have two groups G1 (n=18)and G2(n=15) (33 subjects in total),
and two conditions C1 and C2 (with two levels a and b), I modeled the
interactions as
Interaction 1 - Group x C1 = (G1C1a-G1C1b)- (G2C1a-G2C1b)
Interaction 2 - Group x C2 = (G1C2a-G1C2b)- (G2C2a-G2C2b)
The contrasts entered were
zeros(1,33 ) 0 0 0 0 0 0 1 -1 -1 1 0 0 0 0 for interaction1
zeros(1,33 ) 0 0 0 0 0 0 0 0 0 0 1 -1 -1 1 for interaction 2
What will be the correct contrasts for main effects of C1 and C2?
Thanks in advance,
Sarika.
On Mon, Mar 5, 2012 at 11:18 AM, sarika cherodath <[log in to unmask]>wrote:
> Hello again,
>
> I just would like to mention that i have two levels for each
> condition as well.So C1 has two levels (C1a,C1b), and C2 (C2a,C2b) has two
> levels, in addition to the two groups.
>
> thanks.
>
>
> On Mon, Mar 5, 2012 at 10:57 AM, sarika cherodath <[log in to unmask]>wrote:
>
>> Hello SPMers,
>>
>> I have two groups of subjects (G1, G2) and want to look at
>> the effect of two conditions(C1,C2) and respective group x condition
>> (G1C1,G1C2,G2C1,G2C2) interactions.What is the best method to model this?
>> Will it be valid if I model both groups together using flexible factorial?
>> Any help would be appreciated.
>>
>> Thanks in advance!
>>
>> --
>> Sarika Cherodath
>> Junior Research Fellow
>> National Brain Research Centre
>> Manesar, Gurgaon -122050
>> India
>>
>>
>
>
> --
> Sarika Cherodath
> Junior Research Fellow
> National Brain Research Centre
> Manesar, Gurgaon -122050
> India
>
>
--
Sarika Cherodath
Junior Research Fellow
National Brain Research Centre
Manesar, Gurgaon -122050
India
