I have made an experiment where 20 people had to look at fearfull images vs
neutral images.
Each subject watchedthe
same run 4 times,with 1
parameter varying each time (so in total I have 4 times for the same
run). But I can’t compare the 4 sessions together because they differs from the
previous one by a single parameter. For instance the 3rd session differs from
the 1st one by 2 parameters.
To see if one parameter has an effect, I have done a paired t-test between 2
conditions (time 1 vs time 2 ; time2 vs time 3 ; time 1 vs time 4).
First I would like to know if the paired t-test is appropriate and second, I am
not sure which contrast (F or T) I am supposed to use.
Is it correct to do a F test with the vector [-1 1] (cf. picture attached to this mail) or do I have to complete
for all the columns [-1 1 -1 1 -1 1...] ?
Any help would be more than appreciated!
Thank you very much in advance.
