Hi, please can I get some help with a problem I am experiencing.
I have a single pool of 60 faces which need to appear in pairs without replacement across 30 trials. Faces appear next to each other onscreen. I am having trouble figuring out how to get each face only to appear once as they are appearing randomly on both the right and left side of the screen. As the faces get pulled from the item list they should them be excluded from further use. It makes no difference if they appear left or right as long as its random and only once. But once they appear they should not appear again.
Any help will be appreciated. Many thanks
David Barton
<picture faceleft>
/ items = faces
/ select = noreplace
/ size = (45%, 45%)
/ position = (30,45)
</picture>
<picture faceright>
/ items = faces
/ select = noreplace
/ size = (45%, 45%)
/ position = (65,45)
</picture>
<item faces>
/1="face (1).jpg"
. . . . .
/60= "face (60).jpg
</item>
<trial facetrial>
/ validresponse = ("z", "/")
/ correctresponse = ("z", "/")
/ stimulusframes = [1=faceleft,faceright]
</trial>
<block Election>
/ trials = [1-30 = noreplace(facetrial)]
/ errormessage = true(error,200)
/responsemode=correct
/ preinstructions = (instructions)
/ recorddata = true
</block>