Hello,
I'm running an event related design analysis and am a little confused. I have 4
events. Event 1 is the baseline for Event2 , Event 3 is the baseline for Event
4. Event 2 has 2 possible types, and event 4 has 3 possible types. Therefore I
have 10 conditions. There are also two Orders of these being presented for
each subject, in other words two sessions per subject with different SOAs for
the same conditions of same duration.
If I run an analysis with 6 subjects and each subject has a session with order 1
and order 2 do I need to enter each of 12 sessions individualy to set up the
design? That just seems like alot of work, is there an easy way out? (I
realize if I had one order then I would go through the following just once.)
scans/sessions 12
conditions replicated Yes
timing same No ( since there are two Orders and 36 trials
# of conditions 10
------
Stoich No
SOA variable YES
***
Vector of onset
Variable Duration Yes
duration scan (vector)
***repeat 9 times
---repeat 11 times
Secondly, I have been entering NO for Variable Duration since the duration of
each type of condition is constant, I have found that this is giving me a
design where all 10 conditions are the same length rather than each condition
having a particular length. Therefore for each subject who has 10 conditions, I
would, for example, need to enter duration(scan) as
(0.8 *18) for my vector of condition one and so on for the other 9 conditions.
Is this correct?
Thirdly is it possible to implicitly model the 5 baselines for each of 5
condition implicitly?
thanks so very much, for you help and input,
Maria
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