Experiment:Control group with 70:30 split

Question

Hello :),
could you please advise me how to make randomization of experiment and control group with 70:30 split in the results?
I only have one experiment group and one control group.
Thank you!
Karin

Answer 1

The easiest solution here is to (technically) create 10 experimental groups (codes) in a random generator question and then recode 1..7 to group A and 8..10 to group B.

if (value('RG01') <= 7) {
  put('RG02_01', 1);
} else {
  put('RG02_01', 2);
}

For the above code, you need a random generator RG01 and an "internal variables" question RG02 with one variable RG02_01.