Partial Randomization

Hey, so here’s what I am trying to do:

  1. Display a face with a name (put together as one picture)
  2. Add a RANDOM text about morals underneath

I have each face/name as a separate event and each additional text as a separate event. I need to randomly select one of the moral texts to add to the face, which I’ve done. The problem is that I don’t want the moral texts to repeat.

Is there anyway to make it so once a list of events are randomized each one is only used once?


You could try making your face with name as one event ( so you would probably have to do this outside of superlab ) and create a stimulus list with the moral texts. Make the stimulus list the first event in the trial and the face + name as all the other events in the same trial. Then you’ll want to randomize the events in the trial EXCEPT for the first event ( which is your stimulus list ). Then randomize the trials in the block.

I hope that helps. Let us know about any more questions you have.


Thanks, Hong, that really helped a lot. I’ve never used lists before but they’re amazing, I can’t believe how much time they can save. I did what you suggested with a little twist but I have a different problem now, here are my events:

  1. moral list
    2-6) Faces
  2. name list

I randomized "once per participant " all but the first and last events so it shows a moral, then a random face, then a name. HOWEVER when I test this the pictures of faces keep repeating. I thought randomizing only once per participant would prevent this but for some reason superlab is randomizing everytime a new item from the list is chosen instead of once at the beginning of the experiment like I want. do you know how to fix this?

There was a detail inadvertently left out of Hong’s recommendation: you need a feedback on each of the face+name events to skip the remaining events and move on to the next trial. This will fix the issue with seeing all faces in each trial.

This is incompatible with your second setup of having the names in a separate list, which is why we recommended merging the face+name into a single file/event.

Furthermore, stimulus lists can’t be randomized, so the stimuli from your moral list will always be paired with the same names from your name list. You can randomize the trials after the pairings have occurred, but the lists themselves can’t be randomized.

thanks for your help, Hank. I decided to take your suggestion and combine the names and faces after all. BUT my problem as stated above is still occuring. Even though I have the events randomized as “once per participant” I am seeing faces repeat themselves. I need the faces to be randomized with each text in the list but WITOUT repeats and I can’t seem to find out how to do this. please help!