Adaptive regression parameter estimation in R How would I do parameter estimation and prediction for the adaptive regression model using R, as in the 4th page of the paper linked below?

http://papers.ssrn.com/sol3/papers.cfm?abstract_id=923635

Could anyone clarify this for me?

If you know adaptive regression models very well, share some useful link, or describe the model/parameter estimation/prediction, that would be very helpful.

Thank you so much!
Here is some notes for an R package 'earth' for adaptive regression. This may be useful.

http://cran.r-project.org/web/packages/earth/vignettes/earth-notes.pdf