Hi Jari, That's good to hear - I hadn't made the connection to cca/rda. This will help me find pertinent literature as well.
Many thanks, Marc On Wed, May 23, 2012 at 9:33 AM, Jari Oksanen <jari.oksa...@oulu.fi> wrote: > Marc, > > Basic R stats functions like prcomp have a predict method that can be used > to "predict" (calculate) scores with 'newdata'. This is standard, and has > been in R for ever. Most textbooks of multivariate analysis should handle > this issue. > > In community ecological context, see functions predict.cca and predict.rda > in vegan. These take argument 'newdata' which can be new community data -- > depending on what you want to predict (argument 'type'). Function > calibrate.cca documented in the same help page can be used to predict > values of constraining variables in constrained ordination (CCA, RDA) from > community composition, also with 'newdata' communities. > > Cheers, Jari Oksanen > > ________________________________________ > From: r-sig-ecology-boun...@r-project.org [ > r-sig-ecology-boun...@r-project.org] on behalf of Marc Taylor [ > marchtay...@gmail.com] > Sent: 23 May 2012 10:19 > To: r-sig-ecology@r-project.org > Subject: [R-sig-eco] PCA as a predictive model > > Hello R-sig-ecology group, > > I was wondering if anyone is aware of an example where PCA is used as a > predictive model? A community analysis example might be to predict the PC > values of a sample given its community composition. I had thrown this > question up on a statistics forum ( > > http://stats.stackexchange.com/questions/28916/can-empirical-orthogonal-function-eof-analysis-be-used-as-a-predictive-model > ) > but have gotten hardly any response. I imagined that there are some folks > here that would have some insight into this problem. > > Many thanks, > Marc > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-ecology mailing list > R-sig-ecology@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology > [[alternative HTML version deleted]] _______________________________________________ R-sig-ecology mailing list R-sig-ecology@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
