randomization: show one picture only once in a loop
Hi there,
I have a loop with 2 variables: positive and negative. Each variable have 25 pictures. I want to randomize their sequence but each picture can only be shown once.
I used the full factorial design, but it will list out all the possibilities, which means those pictures will be repeatedly shown.
I really appreciate your help!
Comments
Hi,
Have you tried to make the design without using full factorial design?
See also http://osdoc.cogsci.nl/3.1/manual/structure/loop/.
Hi, how is it that pictures are repeatedly shown? What does "list out all the possibilities" look like exactly? I would think your loop item should show just one variable, with two values positive and negative, cycled 25 times.
Cheers,
Josh
Hi, thank you for the quick response! I basically follow the beginner tutorial to randomize
This is what the loop's split view looks like:
set repeat 0.04
set order random
set description "Repeatedly runs another item"
set cycles 625
set continuous no
set break_if_on_first yes
set break_if never
setcycle 0 n 1
setcycle 0 nn 1
setcycle 1 n 2
setcycle 1 nn 1
setcycle 2 n 3
setcycle 2 nn 1
setcycle 3 n 4
setcycle 3 nn 1
setcycle 4 n 5
setcycle 4 nn 1
setcycle 5 n 6
setcycle 5 nn 1
setcycle 6 n 7
setcycle 6 nn 1
setcycle 7 n 8
setcycle 7 nn 1
setcycle 8 n 9
setcycle 8 nn 1
setcycle 9 n 10
setcycle 9 nn 1
setcycle 10 n 11
setcycle 10 nn 1
setcycle 11 n 12
setcycle 11 nn 1
setcycle 12 n 13
setcycle 12 nn 1
setcycle 13 n 14
setcycle 13 nn 1
setcycle 14 n 15
setcycle 14 nn 1
setcycle 15 n 16
setcycle 15 nn 1
setcycle 16 n 17
setcycle 16 nn 1
setcycle 17 n 18
setcycle 17 nn 1
setcycle 18 n 19
setcycle 18 nn 1
setcycle 19 n 20
setcycle 19 nn 1
setcycle 20 n 21
setcycle 20 nn 1
And this is what the next console's split view looks like:
set duration 0
set description "Displays stimuli"
draw image center=1 file="n[n].png" scale=0.4 show_if=always x=0 y=0 z_index=0
There is another console: (randomize nn)
set duration 0
set description "Displays stimuli"
draw image center=1 file="nn[nn].png" scale=0.4 show_if=always x=0 y=0 z_index=0
I want to show each n/nn only once but in a randomize fashion, if I just write 1-25 on the loop variable, it will run in sequence. How do I shuffle?
Oh, I'm sorry. I shouldn't use full factorial design. It will randomize automatically.
I'm inexperienced with open sesame. Sorry for the question, and thank you for your help!