For my experiment, I need to randomly assign participants to two conditions (of equal size - let’s say 50 participants in each condition). I am building the experiment in the desktop version of PsychoPy, and will be running it on Pavlovia. The participants will be collected through Prolific.
My issue is with getting random assignments to equal-size groups to work online. For the in-person version, I thought of making an excel sheet with pre-randomized conditions that requires us to put in the condition at the beginning. However, that is not acceptable (for us) on Prolific for many reasons.
What did you try to make it work?:
I have tried using a Qualtrics survey but I am unsure how to connect it to PsychoPy later and how to access the variable I made:
I have also made a code that randomizes conditions before the start (in PsychoPy), but upon realizing I cannot ensure equal size conditions I dropped this idea.
I found some leads online, but I am finding it difficult to follow them, so if someone could help me out that would be great.
OS (e.g. Win10): Win11Home
PsychoPy version (e.g. 2024.2.4 Py 3.8): v2023.2.3 Standard Standalone Installation? (y/n) If not then what?: y Do you want it to also run online? (y/n) y
Link to the most relevant existing thread you have found:
I think my post that you have included in your initial question have provided one solution to your problem. For that experiment, I combined Qualtrics with Psychopy. I used the randomizer in Qualtrics to randomize the condition. In order for this to work, I think there are three elements you need to do:
make sure you include a cond variable in Psychopy setup (see below)
It sounds like what you want to do is essentially counterbalancing - which we added a routine for in 2024.1.0. I’d recommend updating to a newer version and giving it a go
