I am trying to write a staircase for a visual perception task. From a previous task I will have calculated a participants particular ‘threshold value’/just noticeable difference value (e.g 40ms), and I am trying to write a programme where I can input the participants threshold value at the start, and then the stair case goes up/down in increments of this threshold (e.g every step up could be 2xthreshold value, and steps down could by 1xthreshold). (I know this probably sounds like a weird request from a psychophysics point of view since I already know their threshold (!), but the reason is I want to utilise a long staircase as a ‘training’ condition to try and improve task performance) Currently my staircase looks like this:
#create the staircase handler
staircase = data.StairHandler(startVal = 15,
stepType = ‘lin’, stepSizes=[3,1],
nUp=1, nDown=1, #will home in on the 80% threshold
I would be grateful for suggestions of what code could be written for the stepSizes parameter that would enable the staircase to go up/down in multiples of the participants’ individual threshold values. My python skills are pretty basic.