Hi,

I'm designing an experiment in which people use the online rating scale in MediaLab to rate a background image. In the one-person condition, the background image will be a Powerpoint slide (converted to .bmp) which shows an image of one person. In the eight-person condition, the background image will be a Powerpoint slide which shows an image of eight persons. Now, because there are eight different person images that I could use in the one-person condition, that means there are 8 possible Powerpoint slides I could use for that condition. Is there any way to randomize the selection of those 8 Powerpoint slides in the one-victim condition? That way, people in the one-person condition would not always see the same image. I have considered just creating a bunch of conditions (where there are 8 different variants of the one-person condition, and then the 8-person condition), but I have another factor in my study with 3 levels (which would multiply the total number of conditions from 6 up to an unwieldy 24). Do you have any suggestions?