between-subject design?

[Aivi47]

What would you like or expect to see?

I would like to create an experiment with 3 different conditions between subjects. Ideally there would be a random allocation of eac participant to one of the three groups. Is this possible with lab.js?

Finally, please tell us which browser you're using (and the version thereof)

I'm using Chrome Version 122.0.6261.111.

[mcfarla9]

If you simply want to assign each session to a random condition, just use Math.random() in lab.js script.

We wanted to do something similar, assigning each subject to one of three conditions, except that we wanted to balance the number of subjects in each group, and Math.random() did not achieve that. In our case we used server-side script (PHP) to keep a count of the subjects and then assign conditions in round-robin fashion. We run our own lab.js study server, otherwise I do not know if we could run our own server-side script.

[Aivi47]

Thank you very much for your answer and explanations!