[R] Dimensionality reduction with proDenICA

Hello, I have a dataset with many variables and I'd like to do dimensionality reduction with Independent Component Analysis. There are many statistical methods to estimate the latent variables of the ICA model. I'm trying the R package "proDenICA" that implements the penalized maximum likeliho

[R] Fitting Hastie's principal surfaces in R

Hello, I need to summarize a three-dimensional dataset through a principal surface that passes through the middle of the data. Principal surfaces are non-linear generalization of the plane created by the first two principal components and provide a non-linear summary of p-dimensional dataset. P

Re: [R] k-nearest neighbour classification

I know that knn.cv(train=predictors.training, cl=classes.training, k=3, prob=TRUE) works but by doing so I fix the tuning paramer k to be 3. Isn't cross validation a technique to choose the optimal tuning parameter trying a range of different values for the tuning parameter? -- View this messag

[R] k-nearest neighbour classification

Hi, I'm trying to perform a cross validation to choose the optimal k in the k-nearest-neighbors algorithm for classification. I'm using the knn function of the package class. Reading the R documentation, I've found out that there

Re: [R] additive proportional odds model in R

Thank you David Winsemius for the answer. With the ambiguous term "additive proportional odds model", I meant the nonparametrical generalization of the parametrical proportional odds model. In other words, I meant to fit a generalized additive model (GAM) with a cumulative logit as link function.

[R] additive proportional odds model in R

Hi all! I'm looking for a way to fit an additive proportional odds model in R since I need to analyse ordinal data. The polr() function of the MASS package of R allows only to fit a linear proportional odds model so I can't use it. The gam() function of the gam package of R allows to fit additive

Re: [R] Strange Bug in R

Thank you all very much for the explanations! -- View this message in context: http://r.789695.n4.nabble.com/Strange-Bug-in-R-tp4713175p4713182.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list -- To U

[R] Strange Bug in R

Hi all. I don't understand why R works this way: > rm(list=ls()) > require(foreign) > dataset <- read.dta("http://www.ats.ucla.edu/stat/data/ologit.dta";) > min(dataset$gpa) [1] 1.9 > min(dataset$gpa)>=1.90 [1] FALSE > min(dataset$gpa)>=1.9 [1] FALSE > min(dataset$gpa)>1.89 [1] TRUE Shouldn't I get