generating random locations

[Aysecan Zeynep Boduroglu]

HI,
We are currently trying to program a visual search paradigm (Find a
rotated T among rotated Ls). Our problem is this particular version of the
task requires you to repeat some of the configurations while generating
new random configurations on all other occations. There are 720 trials, and
360 of these are entirely new, the others are the repetitions of 12
previously generated displays. WE want to look at whether people do learn the
"repeated configurations".

The question is how can we generate random configurations in 360 trials
(for each trial we need to choose 12 locations out of a possible 48
locations where the target and the distractors appear and draw rotated Ts
and Ls on these locations). If you have any suggestions, please let us
know.


thanks,
aysecan


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Aysecan Boduroglu
University of Michigan
Psychology Department
Cognition and Perception
Office : East Hall  4422
Office tel: 763 0008
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