I'm having trouble with randomisation, and your help would be much appreciated:
I have a database of 100 images, along with 5 different measures. The study has 5 blocks. In each block, participants need to be randomly presented with 5 images from this 100 and then randomly presented with 1 of the 5 measures. This then needs to be repeated a further 4 times (so that by the end of the study participants have had all 5 measures, and looked at 5 groups of 5 images - that is, 25 different images in total randomly selected from the 100). Crucially, however, and this is the part I'm struggling with, I don't know how to tell qualtrics not to give the same images or measures twice *accross the different blocks*: e.g. to ensure that if an image or measure appears in block 1, say, it will not be selected to appear in blocks 2, 3, 4, or 5. Does anyone know how this can be done?
'Evenly Presenting' images and measures once won't seem to do it, as this will surely only do this within a block, and will reset when it comes to the next block.
Any help with this would be much appreciated. Thanks so much to you all in advance.
Warm and desperate wishes,
Ryan
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