Millisecond Forums

Hi!

We have an experiment were we want participants to get 18 different trials, and within that we have 2 conditions and 6 trial types (three trials fall into each trial type). We want participants to see 3 trial types (9 trials) in one condition and 3 of the trial types in another condition (if a trial type appears in one condition, we do not want it to appear in the other condition for the same participant). If we want to randomize this as much as possible, how do we group these trials together into blocks without running the risk of having unbalanced condition assignment at the expt level? Or, if we don't group the trials together in a block by trial type, I think we might end up repeating the same trial type in different conditions.


So far we are just counterbalancing it pseudorandomly by hard coding a few different combinations. Here is one counterbalancing condition:


<expt controlandintervention>
/ blocks = [1=noreplace(block.condition1, block.condition2, block.condition3)]
</expt>

<block condition1>
/ trials = [1=playcond1; 2-10=noreplace(c_cap1, c_bottlecap2,c_lid3, c_drinkingglasses4, c_eyeglasses5, c_goggles6, c_bullshorn7, 
c_insthorn8, c_croissant9); 11=trial.whitescreen1 ;12-20=noreplace(i_paper10, i_bedsheet11, i_leaf12, i_globe13, i_hotairballoon14, 
i_rubberballoon15, i_shirtcollar16, i_dogcollar17, i_neckalace18)]
</block>

<trial playcond1>
/ stimulusframes = [1=greenarrowcond1]
/ inputdevice = mouse
/ validresponse = (greenarrowcond1)
/ recorddata = false
</trial>


<picture greenarrowcond1>
/ items = ("play_green copy.jpg")
/ size = (500, 500)
/ position = (50,50)
</picture>

<trial whitescreen1>
/ stimulusframes = [1=whitescreen1]
/ timeout = 3500
</trial>

<picture whitescreen1>
/ items = ("whitescreen.jpg")
/ size = (1000,1000)
</picture>


<trial c_cap1>
/ stimulusframes=[1=c_cap1]
/ timeout = 3500
</trial>

<trial c_bottlecap2>
/ stimulusframes=[1=c_bottlecap2]
/ timeout = 3500
</trial>

<trial c_lid3>
/ stimulusframes=[1=c_lid3]
/ timeout = 3500
</trial>

<picture c_cap1>
/ items = ("capA.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<picture c_bottlecap2>
/ items = ("capB.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture c_lid3>
/ items = ("capC.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<trial c_drinkingglasses4>
/ stimulusframes=[1=c_drinkingglasses4]
/ timeout = 3500
</trial>

<trial c_eyeglasses5>
/ stimulusframes=[1=c_eyeglasses5]
/ timeout = 3500
</trial>

<trial c_goggles6>
/ stimulusframes=[1=c_goggles6]
/ timeout = 3500
</trial>

<picture c_drinkingglasses4>
/ items = ("glassesA.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>


<picture c_eyeglasses5>
/ items = ("glassesB.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture c_goggles6>
/ items = ("glassesC.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>


<trial c_bullshorn7>
/ stimulusframes=[1=c_bullshorn7]
/ timeout = 3500
</trial>

<trial c_insthorn8>
/ stimulusframes=[1=c_insthorn8]
/ timeout = 3500
</trial>

<trial c_croissant9>
/ stimulusframes=[1=c_croissant9]
/ timeout = 3500
</trial>


<picture c_bullshorn7>
/ items = ("hornA.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture c_insthorn8>
/ items = ("hornB.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<picture c_croissant9>
/ items = ("hornC.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>







<trial i_paper10>
/ stimulusframes=[1=i_paper10]
/ timeout = 3500
</trial>

<trial i_bedsheet11>
/ stimulusframes=[1=i_bedsheet11]
/ timeout = 3500
</trial>

<trial i_leaf12>
/ stimulusframes=[1=i_leaf12]
/ timeout = 3500
</trial>

<picture i_paper10>
/ items = ("sheetA.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<picture i_bedsheet11>
/ items = ("sheetB.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture i_leaf12>
/ items = ("sheetC.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<trial i_globe13>
/ stimulusframes=[1=i_globe13]
/ timeout = 3500
</trial>

<trial i_hotairballoon14>
/ stimulusframes=[1=i_hotairballoon14]
/ timeout = 3500
</trial>

<trial i_rubberballoon15>
/ stimulusframes=[1=i_rubberballoon15]
/ timeout = 3500
</trial>

<picture i_globe13>
/ items = ("balloonA.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<picture i_hotairballoon14>
/ items = ("balloonB.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture i_rubberballoon15>
/ items = ("balloonC.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<trial i_shirtcollar16>
/ stimulusframes=[1=i_shirtcollar16]
/ timeout = 3500
</trial>

<trial i_dogcollar17>
/ stimulusframes=[1=i_dogcollar17]
/ timeout = 3500
</trial>

<trial i_neckalace18>
/ stimulusframes=[1=i_neckalace18]
/ timeout = 3500
</trial>

<picture i_shirtcollar16>
/ items = ("collarA.HEIC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>

<picture i_dogcollar17>
/ items = ("collarB.jpg")
/ size = (500, 500) 
/ animation = circle(2000, 2, 0, 600, 375, 50)
</picture>

<picture i_neckalace18>
/ items = ("collarC copy.jpg")
/ size = (500, 500) 
/ animation = path(2000, 1, 35, 50, 65, 50, 50, 50)
</picture>