[R] Great difference for piecewise linear function between R and SAS

[Andrew Robinson]

On Mon, Mar 24, 2008 at 01:09:35PM -0500, Paul Johnson wrote:
> On Mon, Mar 24, 2008 at 8:11 AM, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
> > On 3/24/2008 9:03 AM, zhijie zhang wrote:
> >  > Dear  Murdoch,
> >
> > >   Thanks very
> >
> >  I would use predict() instead.  What you have there doesn't look as
> >  though it uses the B-spline basis.
> >
> >  The reference given in the ?bs help page is a reasonable starting point,
> >  but just about any book that covers splines should handle the B-spline
> >  basis and the linear case.
> >
> >  Duncan Murdoch
> >
> 
> Dear Duncan and others:
> 
> Can you please refer us to an understandable book that explains about
> b-splines?  I've tried a few and the math pretty quickly becomes
> unintelligible to a non-math major.

I think you should try Simon Wood's "Generalized Additive Models: An
introduction in R."  2006 Chapman and Hall. 

I reviewed it recently and I think it's really very good.

Cheers

Andrew

-- 
Andrew Robinson  
Department of Mathematics and Statistics            Tel: +61-3-8344-6410
University of Melbourne, VIC 3010 Australia         Fax: +61-3-8344-4599
http://www.ms.unimelb.edu.au/~andrewpr
http://blogs.mbs.edu/fishing-in-the-bay/