Empirisoft Support

    Welcome to Empirisoft Support
Results 1 to 2 of 2

Thread: Block randomization question

  1. #1

    Block randomization question

    I'm having trouble getting my questionnaire file set up to do the block randomization I'm looking for. I have 20 sets of questions, each with 6 items presented in groups of 3: (a, b, c) or (d, e, f). I want to present participants with one of the (randomly chosen) groups of 3 for each of the 20 sets.

    So each participant should get either (1a, 1b, 1c) OR (1d, 1e, 1f), either (2a, 2b, 2c) OR (2d, 2e, 2f), etc., all the way down to either (20a, 20b, 20c) OR (20d, 20e, 20f).



    I also would like to randomize the order in which they see the 20 items, so participant 1 might get:
    (14a, 14b, 14c); (3d, 3e, 3f); (8d, 8e, 8f); etc.

    ...and participant 2 might get:
    (2d, 2e, 2f); (19d, 19e, 19f); (10a, 10b, 10c); etc.

    Does that make sense? I'd rather not have to make each set of 3 questions (e.g., 1a, 1b, 1c) into a separate questionnaire, because then I would need 40 questionnaires just for this randomization!

    Any suggestions on how to do this?

  2. #2
    Join Date
    Nov 2005
    Posts
    3,328
    I don't see a way around using multiple que files here because you can't use multiple levels of BGR within a single questionnaire file. But on the plus side, it ought to only be 20 not 40.

    You could place all six items for a group within a single que file. You assign the abc items a BGR value of 1 and the def items a BGR value of 2. On the c and f items, you use a skipto value jumping them to an end item in that questionnaire (e.g., a simple blank instruction item with a (d1) parameter). That takes care of which three they see from the six. Then you just randomize the order of those 20 .que files in the experiment (.exp) file.
    Last edited by jarvis24; 04-23-2008 at 05:12 PM.

Similar Threads

  1. Randomization
    By clare66 in forum MediaLab Older Versions: General Questions
    Replies: 5
    Last Post: 02-06-2008, 02:49 PM
  2. Complicated Block Randomization Issues
    By klgreen in forum DirectRT Older Versions: How Do I...
    Replies: 1
    Last Post: 09-19-2007, 02:35 PM
  3. Too much Randomization
    By L4lab in forum DirectRT Older Versions: Troubleshooting
    Replies: 2
    Last Post: 03-31-2007, 05:18 PM
  4. Block Order in output file
    By Gary London in forum DirectRT Older Versions: How Do I...
    Replies: 3
    Last Post: 02-19-2007, 02:58 PM
  5. providing block-level feedback
    By olsza7 in forum DirectRT Older Versions: How Do I...
    Replies: 1
    Last Post: 11-28-2005, 04:41 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •