is it possible in Limesurvey to get a random assignment to different conditions (like control /experimental group)? It should be a equal distribution as possible.
Until today i did it with a javascript code like this:
Code:
varmin=0;varmax=3;var random = Math.floor(Math.random()*(max-min+1)+min);
$('#question1234').hide();
$(document).ready(function(){
document.getElementById('answer1234X123X12').value = random;});
I produced a random number and put it as an answer for a hidden question, so I can refer to this answer later.
I have a similar question. In my survey I have 4 conditions. Via a hidden question ({rand(1,4)}) and linking each question that belongs to one of the 4 conditions through 'token, previous question, value equals ...' my survey already randomly assigns participant to one of the four conditions but that doesn't happens equally. For example, I want that 40 participants are assigned to condition a, 40 participant to condition b ans so on. The technical department of my university says that it isn't possible via Limesurvey so now I have come to you.. I hope that there is a solution, otherwise I think that the only possibility is to manual assign people to one of the conditions with their email address in advance.. Javascript is really a different language for me so please help me.
Well, you can use the {SUBMITID} variable (which is available AFTER the first page submission) and the
JavaScript modulus operator
to load a hidden short-text question with sequential numbers between 1 and 4.
Note though, that the sequential number will increment with every respondent, even those who don't complete the survey.
Add this script to the source of a short-text question:
Code:
<script type="text/javascript" charset="utf-8">
$(document).ready(function(){var submitID ={SAVEDID};// Hide this question
$('#question'+qID).hide();// Find sequential number between 1 and 4 based on the SUBMITIDvar conditionNumber =(submitID %4)+1;// Load the hidden question
$('#question'+qID+' input.text').val(conditionNumber);});</script>
.
Cheers,
Tony Partner Solutions, code and workarounds presented in these forums are given without any warranty, implied or otherwise.
Thank you! I will try to implement what you have said in my survey. I'm sure it works, now I only need to make it work with my technical skills... I will try. Thanks!
I also have a similar issue. I am conducting an on-line research with 12 conditions. I would like each condition to have 15 participants. Thus, can someone please provide me step-by-step instructions on how to set that up; I am new to Lime Survey and to the world of coding.
I would like to use the code posted on the first page but I can't get it working. Do I need to change anything in it like the qID or something like that?
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