Left/Right Stimuli randomisation

Builder
1

I’m trying to run an experiment in builder where a stimulus appears on the left or right hand side of the screen.
I can do this if I pre-select the location of each stimulus, but I want it to be random for each participant.

Is anyone able to help?

3

Hi! You will need to set up a loop. Here are some instructions:
https://www.psychopy.org/builder/flow.html#loops

It’s best to put the position coordinates in an excel file. I attached here an example file of what I used before.
That’s what it looks like in the builder:

image
image580×529 13.3 KB

Hope it helps :slightly_smiling_face:

pconditions1.csv (181 Bytes)

1 Like
4

@jemmasedgmond You can create a random Int in Begin Routine and assign it to stimuli Position field.

randNumber = randInt(-10, 10)
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5

That’s great, thanks!

6

Hi I have the same question, i.e. presenting two components (in my case, texts), one in each side of the screen, and I want this position to be random across participants (so itemA is not always left). I’m not sure I understand the solutions here:
@MartaT : if you set the coordinates in the conditions file, then wouldn’t they always be the same for a given stimulus?
@AliBahaari : could you break that down for a beginner please?
Thanks!