Randomization tool

Hi There,

I need to build a survey that includes branches that are randomized. Basically, if an interviewee answers (a) for question 1, for example, then message (b) or (c) show up, with 50% probability each.

Is this possible to do using Odk?

Thanks!

Should be doable. See
https://groups.google.com/d/msg/opendatakit/kkRxr7tppus/jAT3s7prZDsJ
and https://groups.google.com/forum/#!msg/formhub-users/ndcyBG3I-og/2Q3mqk6XYN4J.

Yaw

··· -- Need ODK services? http://nafundi.com provides form design, server setup, professional support, and software development for ODK.

On Thu, Oct 2, 2014 at 9:49 AM, rafaela@planpp.com wrote:

Hi There,

I need to build a survey that includes branches that are randomized. Basically, if an interviewee answers (a) for question 1, for example, then message (b) or (c) show up, with 50% probability each.

Is this possible to do using Odk?

Thanks!

--

Post: opendatakit@googlegroups.com
Unsubscribe: opendatakit+unsubscribe@googlegroups.com
Options: http://groups.google.com/group/opendatakit?hl=en


You received this message because you are subscribed to the Google Groups "ODK Community" group.
To unsubscribe from this group and stop receiving emails from it, send an email to opendatakit+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Hi Yaw,

Thank you for your help. I am trying to randomize two different groups of questions. Basically, I want some people to see one group and other people to see the other group of questions.

After I collect all the data, I would like to have more or less 50% of the people responding the first group, and 50% responding the other group of questions.

I am still not sure how to do this. Can you help me with that? I attached a file so you can take a look at what I am doing.

Thanks!

Teste_Survey_ODK.xls (38.5 KB)

Attached is a sample for that shows a branch that happens 50% of the
time. The key calculation is: concat(( round(once(random()) * 100, 0)
mod 2 ), " ")

The once() tag ensure that the random value is calculated only once
(e.g., the first time the form is created). If you remove it, the
random value to change each time a form is loaded (e.g, to edit the
form).

Yaw

random.xlsx (20.4 KB)

··· -- Need ODK services? http://nafundi.com provides form design, server setup, professional support, and software development for ODK.

On Fri, Oct 3, 2014 at 11:16 AM, rafaela@planpp.com wrote:

Hi Yaw,

Thank you for your help. I am trying to randomize two different groups of questions. Basically, I want some people to see one group and other people to see the other group of questions.

After I collect all the data, I would like to have more or less 50% of the people responding the first group, and 50% responding the other group of questions.

I am still not sure how to do this. Can you help me with that? I attached a file so you can take a look at what I am doing.

Thanks!

--

Post: opendatakit@googlegroups.com
Unsubscribe: opendatakit+unsubscribe@googlegroups.com
Options: http://groups.google.com/group/opendatakit?hl=en


You received this message because you are subscribed to the Google Groups "ODK Community" group.
To unsubscribe from this group and stop receiving emails from it, send an email to opendatakit+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Actually, you should elevate the once() to the outside of the calculation

once( concat(( round(random() * 100, 0) mod 2 ), " "))

··· On Sun, Oct 12, 2014 at 9:48 AM, Yaw Anokwa wrote:

Attached is a sample for that shows a branch that happens 50% of the
time. The key calculation is: concat(( round(once(random()) * 100, 0)
mod 2 ), " ")

The once() tag ensure that the random value is calculated only once
(e.g., the first time the form is created). If you remove it, the
random value to change each time a form is loaded (e.g, to edit the
form).

Yaw

Need ODK services? http://nafundi.com provides form design, server
setup, professional support, and software development for ODK.

On Fri, Oct 3, 2014 at 11:16 AM, rafaela@planpp.com wrote:

Hi Yaw,

Thank you for your help. I am trying to randomize two different groups
of questions. Basically, I want some people to see one group and other
people to see the other group of questions.

After I collect all the data, I would like to have more or less 50% of
the people responding the first group, and 50% responding the other group
of questions.

I am still not sure how to do this. Can you help me with that? I
attached a file so you can take a look at what I am doing.

Thanks!

--

Post: opendatakit@googlegroups.com
Unsubscribe: opendatakit+unsubscribe@googlegroups.com
Options: http://groups.google.com/group/opendatakit?hl=en


You received this message because you are subscribed to the Google
Groups "ODK Community" group.
To unsubscribe from this group and stop receiving emails from it, send
an email to opendatakit+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

--

Post: opendatakit@googlegroups.com
Unsubscribe: opendatakit+unsubscribe@googlegroups.com
Options: http://groups.google.com/group/opendatakit?hl=en


You received this message because you are subscribed to the Google Groups
"ODK Community" group.
To unsubscribe from this group and stop receiving emails from it, send an
email to opendatakit+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

--
Mitch Sundt
Software Engineer
University of Washington
mitchellsundt@gmail.com