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Is it possible to have some trials occur more frequently?


I am programming a cueing paradigm, following the beginners tutorial. In the tutorial, all conditions occur equally frequently. If I wanted 'valid' trials to occur 80% of the time and 'invalid' to occur 20% of the time, is there a way to do this?


  • sebastiaansebastiaan Posts: 2,989


    Yes, you can use the weight operation of the loop item, which is described here:

    Essentially, you create a column, say w, that indicates how often a particular should be repeated; in your case that would be 4 for valid trials, and 1 for invalid trials, resulting in an 80%/20% ratio. And then you add a line weight w to the script of the loop item.

    Does that make sense?


    There's much bigger issues in the world, I know. But I first have to take care of the world I know.

  • rudalerudale Posts: 2

    Yes that makes perfect sense, thank you!

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