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Randomizing and Instruction screens

  1. #1

    Randomizing and Instruction screens

    Hello,
    I need to randomize between blocks and within blocks. The only problem is that I don't know how to assign the instruction screen a number so that it stays with each block and doesn't become randomized within the block itself. I tried using 0 for wgr and 1 for bgr, but that only keeps the instruction screen in a certain position that does not correspond to the proceeding trials. Visually, it looks like this:
    bgr wgr
    instructions 1 0
    trial1 1 1
    trial2 1 1
    instructions 1 0
    trial3 1 2
    trial4 1 2
    .
    .
    etc.

    thanks for any input.

  2. #2
    jarvis24 Blair Jarvis, Administrator
    Sounds like you are on the right track. WGR value should be 0. BGR value should be the same as the BGR value of the other items it belongs with. In your example, try assigning the second set of instructions and trials 3 and 4 a BGR value of 2.

  3. #3
    In your example, try assigning the second set of instructions and trials 3 and 4 a BGR value of 2.


    If I set the BGR for trials 3 and 4 to 2, then I wouldn't I always receive trials 1 and 2 before trials 3 and 4? I want the blocks to be randomized so that I might receive trial 4 first, or maybe trial 2.

  4. #4
    jarvis24 Blair Jarvis, Administrator
    bgr wgr
    instr1 1 0
    trial1 1 1
    trial2 1 1
    instr2 2 0
    trial3 2 2
    trial4 2 2

    This treats the first three items as a block and the second set of three as a block. The order of the two blocks will be randomized. Then within those blocks, the trial items will be randomized but the instructions will stay put.

    Does that make sense or am I missing something?

  5. #5
    I was under the impression that the bgr needed to remain the same number for it to be randomized (like the wgr column). But I did what you said and it worked! thanks.