08-22-2023, 09:47 AM
Hi! Thanks for the response.
Instead of 4 conditions, I can get away with 3, so for simplicity, I'll go with that. In this instance, every participant sees every condition but what is critical is that every condition occurs in a random order AND the passages occur in a random order AND for each participant, the condition assignment for the passage is random.
So condition order possibility is a matrix of
A, B, C
A, C, B
B, A, C
B, C, A
C, A, B
C, B, A
Passage order is a matrix of
T1, T2, T3
T1, T3, T2,
T2, T1, T3
etc
And then each passage can receive each condition so for any given participant it could look like the below or any space in between.
T1-A, T2-B, T3-C,
...
T1-C, T2-A, T3-B
...
T3-A, T1-C, T2-B
I hope that makes it clearer?
One possibility is to list every combination as a list, but I'm hoping to avoid that as clearly the number of lists would be enormous. I'm hoping to just assign each randomly. So each participant gets assigned the topics in a random order and then when they receive the passage for that topic, they're assigned a random condition for that passage. This might mean the assignment isn't perfectly even as described above (some participants might receive all condition A randomly), but that will ok. I think it will balance out. Though, ideally there would be a way to ensure that after receiving condition A, they can't receive it again.
Instead of 4 conditions, I can get away with 3, so for simplicity, I'll go with that. In this instance, every participant sees every condition but what is critical is that every condition occurs in a random order AND the passages occur in a random order AND for each participant, the condition assignment for the passage is random.
So condition order possibility is a matrix of
A, B, C
A, C, B
B, A, C
B, C, A
C, A, B
C, B, A
Passage order is a matrix of
T1, T2, T3
T1, T3, T2,
T2, T1, T3
etc
And then each passage can receive each condition so for any given participant it could look like the below or any space in between.
T1-A, T2-B, T3-C,
...
T1-C, T2-A, T3-B
...
T3-A, T1-C, T2-B
I hope that makes it clearer?
One possibility is to list every combination as a list, but I'm hoping to avoid that as clearly the number of lists would be enormous. I'm hoping to just assign each randomly. So each participant gets assigned the topics in a random order and then when they receive the passage for that topic, they're assigned a random condition for that passage. This might mean the assignment isn't perfectly even as described above (some participants might receive all condition A randomly), but that will ok. I think it will balance out. Though, ideally there would be a way to ensure that after receiving condition A, they can't receive it again.