I have a 2AFC staircase, with transformed up and down method (2up 1 down) or (2down 1 up), with equal step size (at the beginning there are higher step sizes, at the end there are the lower value). This staircase will be used for detecting the performance of the subjects in a sustained attention task.
I know from the literature that the 2up 1 down staircase should converge at the 70% point of the pychcometric function. But how can I test this? When a subject has done the staircase and I obtain his threshold level, how can I test if this threshold level is equal to a performance of 70%?
How Can I evaluate if the staircase worked properly?