Problem alternating target and attribute trials

[Trefor Aspden]

Hi, I would be really grateful if anyone can help me with the following. I wish
to show a series of 40 stimuli, 20 of which are attribute stimuli and 20 of
which are target stimuli. I wish to randomly determine the order of trials
separately for each participant, but also want to ensure that attribute and
target stimuli appear on alternate trials. I also want to ensure that each of
the 20 target items appears once, and each of the 20 stimulus items appears
once. The way the EPRIME list object is set out does not appear (as far as I
can tell) to support a routine such as this, but there may be a way of doing it
I have overlooked.

Thanks for your help, Trefor



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