Millisecond Forums

OUTPUT STOP SIGNAL TASK


https://www.millisecond.com/forums/Topic8267.aspx

By Guglielmo - 6/20/2012

Hi!


I did not understand how to use the output file for this task!
Which column I have to look at in order to know how many errors the subject has done during the task?



thank you much!



Guglielmo

By Dave - 6/20/2012

Looking at generic "errors" does not make much sense in the context of Stop Signal paradigms which *rely* on people making errors (i.e, being unable to suppress their response at some point during stop trials) to estimate the unobservable stop reaction time. For the % of misses on no-signal trials you'll want to look at expressions.miss. In any case, you'll want to thoroughly review Verbruggen et al. (2008) as cited both in the script as well as on the download page, which covers the variables captured in great detail.


Regards,


~Dave

By Guglielmo - 6/20/2012

Thank you very much Dave!


I have looked at expressions.miss coloumn, but there are only "0" and I'm sure the subject made some errors.... Sad


That strange...



I used the trial version of the software for the  data collection ... could that be the problem???



Thanks for the help!!!




Guglielmo






By Dave - 6/20/2012


I used the trial version of the software for the  data collection ... could that be the problem???



No, that can't be the problem.


I have looked at expressions.miss coloumn, but there are only "0" and I'm sure the subject made some errors.


#1: You'll want to make sure you're really looking at the correct column (expressions.miss) by opening the data file in a spreadsheet application like Excel.


#2: You'll want to look at the last line of data for each subject which will contain the final value across all trials.


By Guglielmo - 6/20/2012

Actually some subjects have digits in this column.... but what is their meaning?
For example... which is the difference between 2,5343 and 2,76567???




Ps. I attached  a .dat file...




Thanks!!!

By Dave - 6/20/2012

It means your subject #17 failed to respond (i.e., produced a 'miss') on 8.45 % of all no-signal trials.