Millisecond Forums

Randomization and Multiple Likert Scales

https://forums.millisecond.com/Topic19270.aspx

By unicornx - 6/18/2016

Hello,
I want to design an IAT experiment in Inquisit whereby participants rate their emotion levels on pairs of images that are randomized. However, I have trouble randomizing the images while keeping the groups intact and including multiple Likert/scales on a screen. Also, how can I time the stimuli so that they are displayed for only 4 seconds? Below is the script that I currently have (without the instructions page): 

<expt>
/ preinstructions = (intro)
/ blocks = [1=likertdisgust;2=likertVCU]
/ groupassignment = random
/ postinstructions = (end)
</expt>

<data>
/columns =[date time subject blocknum trialnum trialcode response latency stimulus]
/format=tab
</data>

<defaults>
/screencolor = (175, 255, 175)
/font = ("Arial", -24, 700, 0, 49)
/txbgcolor=(255,255,255)
</defaults>

<picture disgustqs>
/size = (1000, 500)
/items = disgustqs
/position = (50, 50)
/halign = center
/select = sequence
</picture>

<picture VCUqs>
/size = (1000, 500)
/items = VCUqs
/position = (50, 50)
/halign = center
/select = sequence
</picture>

<item disgustqs>
/1 = "A001.png"
/2 = "A001 VCU.png"
/3 = "A010.png"
/4 = "A010 VCU.png"
/5 = "Sn078.png"
/6 = "Sn078 VCU.png"
</item>

<item VCUqs>
/1 = "Sp009.png"
/2 = "Sp009 VCU.png"
/3 = "Sp026.png"
/4 = "Sp026 VCU.png"
/5 = "Dead Human H022 UVA.png"
/6 = "Dead Human H022 VCU.png"
</item>

<likert Disgust>
/ anchors = [1="not disgusting at all"; 4="very disgusting"]
/ stimulusframes = [1 = disgustqs]
/ mouse=false
/ numpoints=4
/ position= (50, 90)
</likert>

<block likertdisgust>
/ preinstructions=(rate_disgust)
/ trials = [1-6 = disgust]
</block>

<likert VCU>
/ anchors = [1="not disgusting at all"; 4="very disgusting"]
/ stimulusframes = [2 = VCUqs]
/ mouse=false
/ numpoints=4
/ position= (50, 90)
</likert>

<block likertVCU>
/ trials = [1-6 = VCU]
</block>

As you can see, I have the pairs of images displayed sequentially, but I prefer to have them display simultaneously. Please let me know what I can do to solve these problems. Thanks!

By Dave - 6/19/2016

> including multiple Likert/scales on a screen

It is not possible to have multiple <likert> elements on a single screen. A <likert> element is a special kind of <trial>. Only one can be run at a given time, not two or more simultaneously.

If you need several *questions* on a single screen, you need to work with <surveypage>s displaying e.g. several <radiobuttons> instead. (A <surveypage> is also a special <trial> element, but it can display multiple question elements on a single page).

> Also, how can I time the stimuli so that they are displayed for only 4 seconds?

Please see the "How to erase stimuli" topic in the Inquisit documentation:

https://www.millisecond.com/support/docs/v5/html/howto/howtoerase.htm

You need to cover the <picture>s with another stimulus (e.g. a <shape>) after 4000ms via the <likert>'s /stimulustimes.

> As you can see, I have the pairs of images displayed sequentially, but I prefer to have them display simultaneously.

As detailed above, this is not possible using <likert> trials. You can however run the two likerts consecutively while making sure that the 2nd likert (VCU) displays the image corresponding to the first (disgust).

Please see the "How to present stimulus pairs" topic in the Inquisit documentation: https://www.millisecond.com/support/docs/v5/html/howto/howtopairs.htm