[solved] repeating conditions without repeating stimuli
Hi - I'm 3-days new to Open Sesame. And as someone who is very technically challenged - thank you! I think it's a great program.
I have what I think is a straightforward question - but can't seem to resolve on my own, so I'm hoping someone can help. I came across a previous discussion thread, which 'almost' gets me what I want:
http://forum.cogsci.nl/index.php?p=/discussion/610/solved-background-colour-as-variable/p1
I have a very similar experiment with 48 trials (each trial has a unique set of stimuli) and 4 conditions (2x2 design). And I want to make sure that each of my 4 conditions appear equally across all 48 trials - but (similar to the discussion thread) I do not want any of my stimuli repeated. So I have set up my experiment in a very similar way to the one in the discussion thread above - with an 'outer loop' listing all 48 stimuli names, and an 'inner loop' with all 4 possible conditions. I have set the inner loop's cycles to '4' and repeat to '0.25' in order to avoid any repeat stimuli. But it's not quite right - my stimuli are not repeating (which is great!) but I need to make sure that each condition is appears in EXACTLY 25% of trials. That's the bit I can't seem to figure out. I see from the discussion thread it needs a bit of Python inline scripting. Does anyone have any suggestions on what the inline script should be? Or any other suggestions?
Thank you!
Marie
Comments
Hi - I managed to solve the problem. I came across another discussion thread which seemed to do the trick:
http://forum.cogsci.nl/index.php?p=/discussion/1064/solved-inline-script-and-python-code-give-different-results/p1
So... I got rid of my outer loop with the stimuli lines, and replaced it with an inline script (before the loop that cycles my 4 conditions) to create my list of unique stimuli. Then within my trial sequence, I included another another inline script with the pop() function (to get rid of repeats) and exp.set function.
Thanks to everyone sharing their various issues on the discussion forum, the techno-phobe in me is finding OpenSesame very handy!
Hi Marie,
Very good to see you figured things out using the forum; I'll mark this one solved. Good luck with your experiment!
Edwin