psychopy/psychopy — pull request #496 by PieterMoors (2014-01-31 13:43:23+00:00)
Title: BF: correction to fit cumulative normal function 

Fitting a cumulative normal function gave incorrect results on recovering parameters from simulated data. I looked up the function on http://en.wikipedia.org/wiki/Normal_distribution and there seemed to be some differences. I updated to code according to this definition and did so for the inverse function and recovering the parameters from simulated data worked fine.