Community Groups are officially here!
We've released Groups, a new feature that enables us to connect community members of similar industries and interests in a shared, private space. You can check out all of the details here, including information about who can join, how to join, and what Groups are currently offered. Please leave your feedback through this Community Groups Feedback Survey.

How to put randomization function for online experiments

Youjeong
Youjeong MinneapolisCommunity Member Qubie ✭
edited July 13 in Survey Platform

Hello, I want to run an online experiment and have some questions about randomization.


I want participants to take a simple 'decision-making' task based on the information they will be given.

They will be shown two tables that describe two different jobs and will choose one. I also want them to do the same task five times. There will be many rows in one table (Table 1) and one row in the other table (Table 2) as shown below.


Yellow highlights imply treatments that I want to manipulate.

I want to give participants a random wage. Is it possible to randomize wages for Firm A and Firm B following different normal distributions, Wage(firm A) ~ N(A, 0.1); Wage(firm B) ~ N(B, 0.1)?

I want to make sure that wage distribution will be chosen at random sequentially first for Firm A and then for Firm B without replacement. 

As for the second treatment, I want to randomly assign a review to Firm A and Firm B from five pairs of pre-written reviews. How can I assign a pre-written review to one firm and then assign another pre-written review to the other firm without replacement? Also, how can I keep doing this throughout five reps of tasks without replacement? (so that one review shows up only once throughout the entire experiment).


I am wondering whether there is a built-in function/feature in Qualtrics for this!

Thank you so much!

Answers

  • ahmedA
    ahmedA IndiaCommunity Member, XMPN Member Wizard ✭✭✭✭✭

    Please read the support pages on randomizer, embeded data and random number generation.

  • Youjeong
    Youjeong MinneapolisCommunity Member Qubie ✭

    Hello!

    I read all of those pages, but they do not help me.

    Specifically, there are five issues:

    (1) I used the loop & merge function, and it turned out that for the first loop I only can see one row. How can I fix this problem? After the first one, I can see other information except for "Reviews from job search websites." I attached the screenshot.


    (2) I could generate a random number with min and max value for Firm A and Firm B, but I couldn't find how to round the numbers to two decimal places. How can I do this?

    When I put something like this (see below), it says it is invalid.


    (3) And this random number generator doesn't ensure normal distribution I guess? How can I make the random numbers will form normal distribution? I have specific mean values and var for two normal distributions in my mind.


    (4) The last row is never shown. How can I fix this problem? I attached the screenshot.


    (5) I generated two variables (political ideology - left / right) and five vectors for each variable for the second treatment. And then I created 10 choice sets and put them as embedded choice sets. However, it doesn't necessarily mean that I could do what I wanted to do:

    "I want to randomly assign a review to Firm A and Firm B from five pairs of pre-written reviews. How can I assign a pre-written review to one firm and then assign another pre-written review to the other firm without replacement? Also, how can I keep doing this throughout five reps of tasks without replacement? (so that one review shows up only once throughout the entire experiment)."

    Is there a better idea/way to implement this?

    Thank you!