On Wed, 2006-11-29 at 11:40 +1300, Kathryn Baldwin wrote: > Hi > I was wondering if anyone knew how to work out the number of knots that > should be applied to each variable when using gams in the mgcv library? > Any help or references would be much appreciated. > Thanks > Kathryn Baldwin
mgcv works out an optimal number of knots to use, using a Generalised Cross-Validation (GCV) routine. Take a look at: Simon N. Wood. mgcv: GAMs and generalized ridge regression for R. R News, 1(2):20-25, June 2001. And Simon's new book: Simon N. Wood. Generalized Additive Models: An Introduction with R. Chapman & Hall/CRC, Boca Raton, FL, 2006. ISBN 1-584-88474-6. For further info on using mgcv for GAMs. HTH G -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Gavin Simpson [t] +44 (0)20 7679 0522 ECRC & ENSIS, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/cv/ London, UK. WC1E 6BT. [w] http://www.ucl.ac.uk/~ucfagls/ %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
