Hi community,
This is the experimental design:
- there are 6 exercises (A-F) and each of them have two versions (1 and 2).
- First, 3 of the 6 exercises are randomly selected.
- then, it has to be decided whether version 1 or 2 of the exercise is presented. But there is a constriction, each version must be shown at least once and for the third exercise it can be either version. The order of the version and exercises doesn’t matter.
For example, exercise A version 1, B version 2, C version 1 are selected, this is valid. But this combination exercise A version 1, B version 1, C version 1, is not valid and must not occur.
I couldn’t think of a way to implement this constriction. Does any one have an idea?
Thank you in advance.
Kind regards,
Michèle
