Re: [R] comparing fit of cubic spline
On Monday 21 May 2007 16:17, Thomas Reed wrote: I want to compare the fit of a quadratic model to continuous data, with that of a cubic spline fit. Is there a way of computing AIC from for e.g. a GAM with a smoothing spine, and comparing this to AIC from a quadratic model? library(mgcv) AIC(gam(y~s(x))) ## a `generalized aic' since effective df used AIC(gam(y~x+I(x^2))) Cheers ** Tom Reed PhD Student Institute of Evolutionary Biology 102 Ashworth Laboratories Kings Buildings University of Edinburgh Edinburgh EH9 3JT [EMAIL PROTECTED] Tel. 00 44 (0)131 6505462 http://homepages.ed.ac.uk/ecunning/tom.html http://homepages.ed.ac.uk/loeske/tom.html ** [[alternative HTML version deleted]] __ 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. -- Simon Wood, Mathematical Sciences, University of Bath, Bath, BA2 7AY UK +44 1225 386603 www.maths.bath.ac.uk/~sw283 __ 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.
[R] comparing fit of cubic spline
I want to compare the fit of a quadratic model to continuous data, with that of a cubic spline fit. Is there a way of computing AIC from for e.g. a GAM with a smoothing spine, and comparing this to AIC from a quadratic model? Cheers ** Tom Reed PhD Student Institute of Evolutionary Biology 102 Ashworth Laboratories Kings Buildings University of Edinburgh Edinburgh EH9 3JT [EMAIL PROTECTED] Tel. 00 44 (0)131 6505462 http://homepages.ed.ac.uk/ecunning/tom.html http://homepages.ed.ac.uk/loeske/tom.html ** [[alternative HTML version deleted]] __ 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.
Re: [R] comparing fit of cubic spline
Thomas Reed tom.reed at ed.ac.uk writes: I want to compare the fit of a quadratic model to continuous data, with that of a cubic spline fit. Is there a way of computing AIC from for e.g. a GAM with a smoothing spine, and comparing this to AIC from a quadratic model? Why don't you try AIC() on each of the fitted models and see what happens? In general R can compute log-likelihoods and AICs for most fitted model objects ... If it doesn't work, you can post your simple example to the list and get more advice then ... Ben Bolker __ 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.
