How can I randomly assign images to different conditions without replacement | XM Community
Question

How can I randomly assign images to different conditions without replacement

  • 22 March 2019
  • 1 reply
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Hello,
I'm having some troubles building the Qualtrics platform for an experiment. My question is about random assignment without replacement through 12 conditions (randomly presented also). I have seen that other people had asked related questions but I find that my problem is a bit different, so I'll try to be super clear:

I have created an experiment in which participants will be randomly presented with 12 conditions (all participants are presented with all conditions) and they will have to answer two questions in each condition. However, each condition can take 4 "condition forms", and participants will be presented only with one (randomly picked) of those forms. So, although in total participants see 12 conditions, in reality our qualtrics have 48 blocks, and 12 randomizers -each with the 4 forms of the specific condition).

Now our problem is the following: In each of the possible condition forms, we would like to pair an image (from a pool of 48, so there is one for each form). However, we would like to show each image only once, so if a participant sees image 1 in condition form 1, he/she wont be see image 1 in any other condition form (so no replacement). Do you know or have any suggestions on how we could do something like this?

Thanks a lot in advance,
Cheers

1 reply

Userlevel 7
Badge +11
You can nest branches into your randomizer and use a conditional statement to make sure it hasn't been used before.

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