Hi,
I have a working version of a program I intend to use for teaching. The aim is to demonstrate the sensitivity to the number and locations of knots when using spline functions in linear regression.
A brief description and video can be found here
http://www2.le.ac.uk/Members/pl4/software/codea/spline-touch
And the code can be found here.
http://www2.le.ac.uk/Members/pl4/software/codea/spline-touch-code
Happy to receive any feedback.
Paul