Randomization without replacement | XM Community
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Dear Qualtrics community,
in our study we have 15 pictures and 15 questions and we would like to combine them into 15 blocks with one picture and one question each. We would like to randomize them without replacement so that none of the pictures and questions show up more than once for one participant. Furthermore, the combinations of pictures and faces should be randomized for every participant.  Is there a way to randomize them like this or do we have to create every combination (15x15) of a question and a picture separately and randomize them afterwards?
Thank you very much in advance for your help!

Just put the 15 blocks in a randomizer... It will display them in a random manner without replacement.


Dear Ahmed,
thank you very much for your answer. I was wondering if I could also get a randomized combination of pictures and questions across all participants, to make sure each participant is shown different combinations? In other words: I would like Qualtrics to generate the 15x15 "sets" of possible combinations of 15 questions and 15 pictures to show each participant a unique set.


Using the inbuilt functionality, that won't be possible. However, you can download the randomized order to see what was shown to each participant.
Also, it won't be 15x15 sets, it would be something closer to 15! x 15! sets.


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