On Nov 05, 2011 at 11:01pm Francisco Mora Ardila wrote: > But a problem arised with the predict function: it doesn´t seem to work > with an object > from dudi.mix and I dont understand why.
Francisco, There is no predict() method for dudi.mix() or for any of the dudi objects in ade4. I don't see why you can't get around this by doing something like the following, but you need to take account of any scaling/centring that you might do to your data before calling dudi.mix(). ## Does a dudi.mix on continuous data, so really equals a dudi.pca/princomp/PCA library(ade4) data(deug) deug.dudi <- dudi.mix(deug$tab, scann=F, nf=2) tt <- as.matrix(deug.dudi$tab) %*% as.matrix(deug.dudi$c1) ## see note below qqplot(deug.dudi$li[,1], tt[,1]) qqplot(deug.dudi$li[,2], tt[,2]) deug.princ <- princomp(deug$tab, cor=T) qqplot(predict(deug.princ)[,1], tt[,1]) ## scaling not accounted for: deug.princ <- princomp(deug$tab, cor=F) qqplot(predict(deug.princ)[,1], tt[,1]) rm(tt, deug.dudi, deug.princ) Note that in the code given above, "as.matrix(deug.dudi$tab) %*% as.matrix(deug.dudi$c1)" is based on how stats:::predict.princomp does it. Regards, Mark. ----- Mark Difford (Ph.D.) Research Associate Botany Department Nelson Mandela Metropolitan University Port Elizabeth, South Africa -- View this message in context: http://r.789695.n4.nabble.com/testing-significance-of-axis-loadings-from-multivariate-dudi-mix-tp3994281p3995350.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org 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.
