Thank you Jesper for the very good insights on my design- a final
question please wrt
> That is to have three different EV's modelling your two event types.
> Define one for valid cues, having a constant duration and magnitude
> (columns 2 and 3) and another one for invalid cues. Finally you
> define a third event-type which models both valid and invalid cues
> modulated by mean-corrected reaction times. This third event-type
> would the model RT modulations that are common to the two types
> while leaving any categorical difference in the two other EVs
according to this my EVS would be valid, invalid, search RT
when defining the EV for the search RT - what do you mean by mean
corrected RTs? do you mean that each individual RT on each trial event
is divided by the mean of RT (i.e. the valid or the invalid RT
accordingly)
also, if I only do one EV as search RT - 3 column specification- how
can FSL know whether each RT is linked to a valid or invalid trial? I
guess this is simply because the first column for the onset of the
valid and invalid events matches - or should I do 2 EVS instead one
for search valid RT and another for search invalid RT - but perhaps
this does not make any difference
lastly, how about the memory RTs? Can I just ignore these in the
model specification. My main aim s to compare Valid>Invalid activity
and this is not related to the memory RT but may only be related to
the search RT---on the other hand, it is true after the search
response, there followed a memory response, and perhaps this should be
included in the model?
hope this is not much of a hassle;
best wishes!
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