[Eeglablist] Error in Calculating Difference Waves

[Arnaud Delorme]

Dear Raechel,

there are 3 possibilities to get around your problem:

1) keep only the same common channels in all the datasets. I agree that 
this is not optimal.

2) create a STUDY, import your 4 datasets and interpolate all missing 
channels when pre-computing ERPs (simply check the box). In this menu, 
you may also remove artifactual ICA components which can be handy. This 
is also optimal if you want to compute statistics.

3) create a STUDY and do not interpolate missing channels (you may still 
remove artifactual ICA components).

Best,

Arno

Raechel Steckley wrote:
> I am a relatively new user (1st year grad student at UCD) of EEGLAB.  I 
> am trying to use the GUI to make a difference wave between correct and 
> incorrect trials in 2 participants.  After loading the appropriate 
> datasets and inputting to Average Dataset 2 4 and average and subtract 
> dataset 1 3, the gui returns an error message that dataset three contains 
> a different number of channels than the other datasets and quits running 
> the pop_comperps at that point.
>
> My question is how to get around this.  All of the subjects we are using 
> have a different number of channels to average across, depending on which 
> channels we've removed during preprocessing.  
>
> Any help is greatly appreciated.
>
> Raechel Steckley, B.S, B.A.
> Graduate Student
> Department of Psychology
> University of California, Davis
>