Why doesn't the trial condition expression work?

I have an experiment with 12 trials, each which needs to be presented 10 times. I’m working with stimulus lists, with a maximum list length of about 100 items, so my assumption is that if I just let the experiment run to completion there will be 1200 trials. I have tried to use the condition expression for each trial “Number of trials this trial has been presented is less than 10” but it doesn’t seem to work. I ran into a similar problem on a previous test experiment when trying to limit the number of times a block was presented and was directed to use the block macro instead, but there isn’t a trial macro to turn to. The closest I can get to the experiment I want is probably just to use a block macro to limit the total number of trials in the block to 120 but that won’t give an even distribution.

Regards,

Wakefield

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Hello Wakefield,

I have posted a new experiment in the newly minted demos forums, seehttp://community.cedrus.com/showthread.php?t=465
I hope this helps.

Hisham.

Thanks for that. I was starting to wonder whether that was the problem. Because I’ve used stimulus lists I don’t have 12 trials to run 10 times each, I have nearly 1200 trials and SuperLab is trying to run each one 10 times each, so I’m getting 12000 trials.

So is it not possible to have each of my 12 trial types run exactly 10 times using 10 random items from a longer stimulus list?

I thought I had a solution for you based on twelve codes with values specifying whether a trial had been presented, but decisions based on this information can only be done at the block level. You also need to make a decision based on the type of trial coming up next, but decisions based on that information can only be done at the trial level. As a result, I don’t believe there’s a way to automate this with SuperLab 4.0.