UNDERSTAND HOW PSYCHOMETRIC FUNCTIONS WORK! 1) Start playing with the function parameters to get some intuition about their roles, 2) Then play with the parameters generating the simulated data, 3) Finally challenge yourself to manually fit the presented data and learn how to select the most appropriate stimulus levels and the right psychometric functions when collecting your experimental data. This widget will be included in the iBooks User Guide of our Psykinematix software! Feel free to try it and provide feedback at: firstname.lastname@example.org. And let us know if you like to get access to an early version of this User Guide in the iBooks textbook format available for iPad only.