Dear experts,
I've specified a factorial design for between groups analysis (SPM5). The design
matrix has 5 conditions each for 2 groups; so it goes like ;
(condition 1, group 1) (condition 2, group 1) (condtion 3, group 1) (condition
4, group 1 ) (condition 5, group 1) (condition 1, group 2) (condition 2, group
2) (condition 3, group 2) (condtion 4, group 2) (condition 5, group 2)
It has 10 cells all together. Now I'm trying to set up some contrasts in order
to compare group 2 over group 1 (i.e., group2 > group1) for different
conditions. What makes it difficult is that the first two conditions are
'baseline' conditions employed for subtraction purpose for each of the latter
three 'active' conditions. Hence, I need to subtract condition 2 (ignore
condition 1) from either condition 3 or 4 or 5 for each groups, before
comparing between groups.
How shall I specify my contrasts? - eg. if I were to compare 'group 2 > group 1'
for 'condition 3 > condition 2', can I assign contrasts of
[0 -1 1 0 0 0 1 -1 0 0] and [0 1 -1 0 0 0 -1 1 0 0] for two-tailed t-test?
I know it's a freaky email and thank you so much if anyone can please reply with
something !!!!!!!!!!!!
Yerina
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