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Hi Folks,

probably an easy question, but I didn’t find an already answered question here in the forum. 
In the internet world it is also known as AB-Split Test. If the user start the questionaire he/she schould be RANDOMIZLY send to question group A or group B. After he answered the question the questionaire is over. He will NOT be sent to the the other group. Is that possible? 
Why am I not doing it with randomization of two questions. Reason: in question group A I ask one single open question. In group B I will randomizly show one out of 5 questions which must be answered with Yes/No. 
I know how to ranomize the questions in group B but i don't know how to randomly send the user to group A or B.

Thanks for your help.

You have to use a question of type "equation" (e.g. "randnum") where you create a random number (1-2)
{if(is_empty(randnum),rand(1,2),randnum)}

The first group gets the "condition": randnum==1
The second group: randnum==2

Joffm

Hey Joffm,

thx. But it doesn't work. After the start of the questionaire it is not doing anything. Where have I made the mistake? See screenshots.
Thx for your support.

How can you imagine this to work?
You create the random number inside the group that depends on it.

Joffm

Not sure if we talk about the same questionnaire. I think I understand how to create a random number inside a group. But I need the random number „outside“ the group to select either group A or B and not a question in a group. Maybe this drawing helps. 

That is what I tried to say.
You create the random number inside a group that depends on this number.
How do you expect this to work?
The "Gruppenrelevanz" (um es einmal auf Deutsch zu sagen) is set to:"randnum==1".
But this value isn't existing at this point. You create it inside this group.

You have to create it outside (and before) the two depending groups.
Exactly as you draw it.
4 Groups:
1. Start group with some general questions - and the creation of the random number(s).
2. a. Question A group (randnum==1)
2. b. Question B group (randnum==2)
3. ( maybe) End group with some general question

And you do not need two groups A/B for your scenario.
You can set all these 6 questions into one group
As said before create both rabdom numbers in Start group
Then
1. Start group with some general questions - and the creation of the random number(s).
2 . Experimental group
2.a. Question A (randnum==1)
2.b.1. Question B1 (randnum==2 AND gleichung==1)
2.b.2. Question B2 (randnum==2 AND gleichung==2)
...
3. Rest of questionnaire
​​​​​​​
That's all.
Joffm

Hi Joffm,

you made my day. Thank you. Version one is working. But I am always curious about learning something new and I tried also version 2. But I don't make it work. Would you be so kind and have a look at it one last time? Creating the numbers in the frist group is working fine. But then it is not choosing anything from group 2. What is the group condition? I tried nothing, AND and OR but no question is showing up. See screenshot.

One final last question: beside randomization, is there a way of equally splitting up the two pathways? User 1 gets question A, user 2 gets question B, user 3 gets question A, user 4 gets question B and so on.

Cheers, Karsten

Dann schick den lss export

User 1 gets question A, user 2 gets question B, user 3 gets question A, user 4 gets question B and so on.

You may read this.
[url] forums.limesurvey.org/forum/german-forum...ng-zu-fragen-gruppen [/url]
Joffm

And seeing your screenshot:
Why are there 5 questions 2A-2E
Why not only one with "Würden Sie {15+randfrage2*5} bezahlen?"

der Export...

Typical GIGO (Garbage in - Garbage out) 

1. There was HTML code in your equation "randfragenAB"
 
NEVER copy/paste something from a word processing program directly, only plain text.

2. "randfrage2" was not an "equation", but still "long text"

Joffm