Millisecond Forums

Hi,

I am trying to create a script that shows participants one pair of images (stimuli image and reference image) and asked them to choose which one is bigger. I have 5 stimuli images and 1 reference image. I try to make it counterbalanced so participants will see equal amount of each stimuli image. Is there a way to counterbalanced this?

Here is my script:

<defaults >
/ screencolor = black
/ txcolor = white
/ txbgcolor = black
/ windowaspectratio = (4,3)
</defaults>


<values>
/completed = 0
/stiminterval = 0
/ aset = 1
/a1=0
/b1=0
</values>

<parameters>
/trialtimeout=10000
/instructiontime=2000
/breaktime=30000
</parameters>


=============================================================================
Instruction page
=============================================================================
<instruct instruction>
/ timeout = parameters.instructiontime
/ fontstyle = ("Arial", 4.5%, false, false, false, false, 5, 1)
/ screencolor = black
/ txcolor = white
/ windowsize = (100%, 100%)
</instruct>


<page instruction1>

              Welcome
^^In this task two pictures containing different portion size will appear on your screen.

^^Please answer the question 'Which one of the pictures has a larger portion ?' by pressing 'F' for the first one and 'J' for the second one.

^^You will have 50 comparison pairs and then a break of 30 seconds.

^^ You will perform a practice trial containing 6 comparison pairs before starting the real test.

^^   Press the space bar to start your practice session!

</page>

<page instruction2>

^^^^^         Get ready for another trial !

^^^^         Press the space bar to start

</page>


<item poolA>
/1="Chips1.jpg"
/2="Chips2.jpg"
/3="Chips3.jpg"
/4="Chips4.jpg"
/5="Chips5.jpg"
/6="Choco1.jpg"
/7="Choco2.jpg"
/8="Choco3.jpg"
/9="Choco4.jpg"
/10="Choco5.jpg"
/11="Yoghurt1.jpg"
/12="Yoghurt2.jpg"
/13="Yoghurt3.jpg"
/14="Yoghurt4.jpg"
/15="Yoghurt5.jpg"
</item>

<list chips_set1>
/ items = (1,2,3,4,5)
/ selectionrate = always
</list>

<list Chipsitemnumbers1>
/ items = (list.chips_set1.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<list choco_set1>
/ items = (6,7,8,9,10)
/ selectionrate = always
</list>

<list Chocoitemnumbers1>
/ items = (list.choco_set1.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<list Yoghurt_set1>
/ items = (11,12,13,14,15)
/ selectionrate = always
</list>

<list Yoghurtitemnumbers1>
/ items = (list.Yoghurt_set1.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<picture a1>
/ items = poolA
/select=values.a1
/size= (50%,50%)
/position=(50%,50%)
</picture>

<item poolB>
/1="Chips6.jpg"
/2="Chips7.jpg"
/3="Chips8.jpg"
/4="Chips9.jpg"
/5="Chips10.jpg"
/6="Choco6.jpg"
/7="Choco7.jpg"
/8="Choco8.jpg"
/9="Choco9.jpg"
/10="Choco10.jpg"
/11="Yoghurt6.jpg"
/12="Yoghurt7.jpg"
/13="Yoghurt8.jpg"
/14="Yoghurt9.jpg"
/15="Yoghurt10.jpg"
</item>

<list Chips_set2>
/ items = (1,2,3,4,5)
/ selectionrate = always
</list>

<list Chipsitemnumbers2>
/ items = (list.Chips_set2.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<list choco_set2>
/ items = (6,7,8,9,10)
/ selectionrate = always
</list>

<list Chocoitemnumbers2>
/ items = (list.choco_set2.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<list Yoghurt_set2>
/ items = (11,12,13,14,15)
/ selectionrate = always
</list>

<list Yoghurtitemnumbers2>
/ items = (list.Yoghurt_set2.nextvalue)
/ selectionmode = values.aset
/ selectionrate = always
</list>

<picture b1>
/ items = poolb
/select=values.b1
/size= (50%,50%)
/position=(50%,50%)
</picture>

<list asetnumbers>
/ poolsize = 1
</list>

===========================================================================================
Reference image
============================================================================================

<picture Chipsreference>
/items=("Chips0.jpg")
/size= (50%,50%)
/position=(50%,50%)
</picture>

<picture Chocoreference>
/items=("Choco0.jpg")
/size= (50%,50%)
/position=(50%,50%)
</picture>

<picture Yoghurtreference>
/items=("Yoghurt0.jpg")
/size= (50%,50%)
/position=(50%,50%)
</picture>



<text questions>
/ items = ("Which one of the pictures has a larger portion?")
/ fontstyle = ("Arial", 5%, false, false, false, false, 5, 1)
/ valign = top
/ halign = center
/ position = (50,20)

</text>

<Text ChoiceA>
/ items = ("Press F= First picture")
/ fontstyle = ("Arial", 4.44%, false, false, false, false, 5, 1)
/ valign = center
/ halign = center
/ position = (20,50)
</text>

<Text ChoiceB>
/ items = ("Press J= Second picture")
/ fontstyle = ("Arial", 4.44%, false, false, false, false, 5, 1)
/ valign = center
/ halign = center
/ position = (75,50)

</text>

========================================================================================================
Chips trial
========================================================================================================

<trial Chipsa1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.chipsitemnumbers1.nextvalue;]
/ stimulustimes = [0=a1;2000=clearscreen;2001=chipsreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Chipsa2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.chipsitemnumbers1.nextvalue;]
/ stimulustimes = [0=chipsreference;2000=clearscreen;2001=a1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Chipsb1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Chipsitemnumbers2.nextvalue;]
/ stimulustimes = [0=b1;2000=clearscreen;2001=chipsreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>

<trial Chipsb2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Chipsitemnumbers2.nextvalue;]
/ stimulustimes = [0=chipsreference;2000=clearscreen;2001=b1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>


========================================================================================================
Choco trial
========================================================================================================

<trial Chocoa1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.chocoitemnumbers1.nextvalue;]
/ stimulustimes = [0=a1;2000=clearscreen;2001=chocoreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Chocoa2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.chocoitemnumbers1.nextvalue;]
/ stimulustimes = [0=chocoreference;2000=clearscreen;2001=a1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Chocob1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Chocoitemnumbers2.nextvalue;]
/ stimulustimes = [0=b1;2000=clearscreen;2001=chocoreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>

<trial Chocob2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Chocoitemnumbers2.nextvalue;]
/ stimulustimes = [0=chocoreference;2000=clearscreen;2001=b1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>

========================================================================================================
Yoghurt trial
========================================================================================================

<trial Yoghurta1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.Yoghurtitemnumbers1.nextvalue;]
/ stimulustimes = [0=a1;2000=clearscreen;2001=Yoghurtreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Yoghurta2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.a1 = list.Yoghurtitemnumbers1.nextvalue;]
/ stimulustimes = [0=Yoghurtreference;2000=clearscreen;2001=a1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("F")
</trial>

<trial Yoghurtb1>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Yoghurtitemnumbers2.nextvalue;]
/ stimulustimes = [0=b1;2000=clearscreen;2001=Yoghurtreference;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>

<trial Yoghurtb2>
/ ontrialbegin = [
values.aset = list.asetnumbers.nextindex;
values.b1 = list.Yoghurtitemnumbers2.nextvalue;]
/ stimulustimes = [0=Yoghurtreference;2000=clearscreen;2001=b1;4000=clearscreen;4001=questions,choiceA,choiceB]
/ beginresponsetime = 4001
/ validresponse = ("F","J")
/ correctresponse = ("J")
</trial>

=================================================================================================================
Break
================================================================================================================

<clock timer>
/ format = "mm:ss"
/ mode = timer
/ erase = false
/ position = (50%, 50%)
/ resetrate = block
/ txbgcolor = black
/ txcolor = white
/ size = (100,100)
/ position = (50,60)
/ timeout = parameters.breaktime
</clock>

<text break>
/items=("Please have a break")
/ fontstyle = ("Arial", 6.67%, false, false, false, false, 5, 1)
</text>

<trial break>
/stimulusframes=[1=break, timer]
/timeout= parameters.breaktime
</trial>

===================================================================================================
Block
======================================================================================================

<block chipsblock>

/ trials = [1-50=noreplace(chipsa1,chipsa2,chipsb1,chipsb2);51=break]
/ preinstructions = (instruction2)
</block>

<block chocoblock>
/ trials = [1-50=noreplace(chocoa1,chocoa2,chocob1,chocob2);51=break]
/ preinstructions = (instruction2)
</block>

<block Yoghurtblock>
/ trials = [1-50=noreplace(Yoghurta1,Yoghurta2,Yoghurtb1,Yoghurtb2);51=break]
/ preinstructions = (instruction2)
</block>

<block practice>
/trials= [1-2=noreplace(chipsa1,chipsb2);3-4= noreplace(chocoa2,chocob2);5-6=noreplace(Yoghurta1,Yoghurtb2)]
/ preinstructions = (instruction1)
</block>


==================================================================================================
Experiment
=================================================================================================

<expt study>
/ blocks = [1=practice; 2-7=noreplace(Chipsblock,Chocoblock,Yoghurtblock)]
</expt>

==================================================================================================
Data
==================================================================================================

<data>
/columns = (build, computer.platform, date, time, subject, group, blockcode, blocknum, trialcode, trialnum,
stimulus,stimulus,stimulus,response, correct, latency)
/ separatefiles = true
</data>