Figure A1.

Illustration of the procedure used to extract the threshold value from a divergent staircase. (a) The solid line represents the behavior of the divergent staircase, while the dotted line shows a standard staircase for reference. (b) Trials are sorted into bins with respect to the scale parameter, with each bin counting the percentage of correct answers in that group of trials. The distribution is then fitted against a sigmoid curve (solid line), and the parameter value corresponding to 70.7% is extrapolated (dashed lines).