Great difference for piecewise linear function between R and SAS
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/