[R] bilinear regression

[Crabb, David]

I think this is an easy question, but I would be grateful for any advice
on how to implement this in R.

I simply have a response variable (y) that I am trying to predict with
one explanatory variable (x) but the shape of the scatter plot is
distinctly bilinear. It would be best described by two straight lines.
Is there a way of fitting a linear model to give me a bilinear fit and
(more importantly) automatically determine the 'cut off' point? I would
also want some statistic to convince myself that the bilinear fit is
better.

Many thanks for your help.

David


Dr. David Crabb
Department of Optometry and Visual Science,
City University, 
Northampton Square, London EC1V OHB
Tel: 44 207 040 0191   d.crabb at city.ac.uk
http://www.city.ac.uk/optometry/html/david_crabb.html