creating random pairs without replacement | Experience Community
Skip to main content

creating random pairs without replacement

  • November 16, 2022
  • 2 replies
  • 152 views
M

Hi there -
I have a study in which I need to present pairs of stimuli to which I would like to ask participants to respond independently to each stimulus in the pair. Then, I would like to show a new pair comprised of the remaining stimuli in the set (this is the "without replacement part"). I only have between 24-56 stimuli in total, so it's not a massive job, but the number of possible pairs is high and I don't want to have to do this manually. Any help?

2 replies

Deepak
QPN Level 8 ●●●●●●●●
Forum|alt.badge.img+46
  • Deepak
  • November 16, 2022

maleien
Try creating two multiple choice question and randomize the choices(include even number of stimuli in each question as choices) in them and hide the two questions.
Post which you can use option wise pairs of each of multiple choice question E.g. Option 1 of question1 and Option1 of question2. It should create random pairs and should accommodate your logic.
Hope it helps!

TomG
Level 8 ●●●●●●●●
Forum|alt.badge.img+27
  • TomG
  • Level 8 ●●●●●●●●
  • November 16, 2022

maleien ,
You can do this:

  1. Add a MC question with all your stimuli. Add advance randomization to only display half of them evenly presented. Add JS to hide and/or click next.

  2. On next page, add a MC question and carryforward the non-displayed choices from (1) above. Add JS to save the displayed stimuli to embedded data fields (stimulus1....stimulusN) and click next. (JS shown below)

  3. Add a loop & merge block with your two questions. Base the loop on the displayed choices in (1) above. Field 2 will be the embedded data fields set in (2) above (e.g., ${e://Field/stimulus1} where 1 is the loop number).

JS for (2) above:
Qualtrics.SurveyEngine.addOnReady(function() {
  jQuery("#"+this.questionId+" label.SingleAnswer>span").each(function(i) {
  Qualtrics.SurveyEngine.setEmbeddedData("stimulus"+(i+1),jQuery(this).html());
  });
  this.clickNextButton();
});
You'll probably want to define the embedded data fields stimulus1 through stimulusN at the top of the survey flow so are saved in your response data.

Terms & ConditionsAccessibility statement