Show a limited number of random options in array questions

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7 months 4 weeks ago #161772 by jamarin
jamarin created the topic: Show a limited number of random options in array questions
I have a long list of Items (rows) in an array question. But I want to show only ten (or whatever other number) of options, at random, each time the question is presented to a respondent.
Randomize options it is not enough because always shows the long list. And limit the number of max or min reponses neither solve my problem. Because I want to show each time only a sort set of the original options.
(I have lots of respondents and don't need to burden to all the respondents asking them all the questions. But I want to collect enough answers for all of the options)

I have considered to split the list in several sections and show the sections at random. But it is not good for me because I need that all the options had the same probability to be presented and in different combinations (not always the same set of options together).

As far as I know, it is not possible to set filter (advanced option in array type question) to select/exclude at random a number of options. You need to specify which ones

The Issue can be solved if there is a way to complete automatically (a hidden question) a multiple choice question with random selection of the options. I don't know how to do it, but if anybody can solve this, then I can use this multiple choice question to filter the array

Regards,

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7 months 4 weeks ago #161773 by Joffm
Joffm replied the topic: Show a limited number of random options in array questions
Hi,
how long is your list?
Two rough ideas:
Less than 52 items
By EM create a string of ten random characters A-Z, a-z like "DGHOQTbfhr".
Then display:
Subquestion 1, if string contains "A" (strpos(mystring,"A")===true)
Subquestion 2, if string contains "B"
Subquestion 3, if string contains "C"
...
Subquestion 27, if string contains "a"
Subquestion 28, if string contains "b"

More than 52 items:
create a string of length(itemcount) (str_repeat("0",itemcount))
at random set ten positions to "1".
Then display:
Subquestion 1, if string contains "1" at position 1 (substr(mystring,0)=="1")
Subquestion 2, if string contains "1" at position 2 (substr(mystring,1)=="1")
...


As said, just two ideas

Joffm


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The following user(s) said Thank You: jamarin

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7 months 4 weeks ago #161785 by jamarin
jamarin replied the topic: Show a limited number of random options in array questions
Thanks Joffm, my list has 62 elements, then I am going to test the second one (and also is a more general workaround that I can reuse with any number of subquestions in the future)

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7 months 3 weeks ago #161814 by Joffm
Joffm replied the topic: Show a limited number of random options in array questions
Hi,

well, in your case you have about 2* 1011 options to select 10 out of 62.

A proposal to create your string.
Do it in EXCEL and add it as ATTRIBUTE to the participants list.

Joffm


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