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Staircase -- can you adjust up for correct values and down for incorrect?

Hi
I’m new to PsychoPy and trying to use a Staircase to adjust stimulus values UP on correct answers and DOWN on incorrect. My code works fine when I use Staircase to adjust down with correct answers and up on incorrect. I’ve tried kludgy things like putting negative values in the excel file containing my staircase stepSizes, but then MinVal and MaxVal don’t work. I can’t be the only person who ever wanted to do this? I can’t find older questions about this anywhere. Thanks in advance.

Hi,

Did you ever find an answer to this - I’m trying to set up something similar in the builder: I’m looking to measure a simple noise threshold by adding noise to a stimuli, so a correct answer should INCREASE the value in the staircase.

Seems like there should be a simple answer here. I’m currently cludging it with a line of code to subtract the new staircase value from a preset maximum noise level before each trial (so 0 is maximum noise and high numbers are easy), but this feels like the wrong way to do this.

Cheers,

Martin

Hi I never got any kind of feedback on it, I tried cludging it a bunch of different ways but couldn’t get it to do what I wanted using the staircase prefabs. I didn’t try the approach you did, defining some maximum number and then subtracting, but I kind of decided I just wouldn’t do it in PsychoPy because I didn’t want to just write the whole thing from scratch in Python to do it.

I don’t know much about using staircases in PsychoPy, but could you just take the value it returns and manipulate it with some arithmetical operation? e.g. take its inverse, subtract it from some maximum value, etc?

Hi Michael,

Yes, that’s exactly what I am doing. It gets the job done, but it would seem like such a common requirement (measuring a noise threshold by staircase), that I feel I must be missing a simpler, built-in, solution.

Cheers,

Martin