similar to: lda

Dear R users, I want to do discriminant analysis on my data. I have successfully followed the discriminant analysis in V & R on the iris data: > ir <- rbind (iris3[,,1],iris3[,,2],iris3[,,3]) > ir.species <- c(rep("s",50),rep("c",50),rep("v",50)) > a <- lda(log(ir),ir.species) > a$svd^2/sum(a$svd^2) [1] 0.996498601 0.003501399 > a.x <-

Hi, I am using the lda function from the MASS library. I would to find the decision boundaries of each class and subsequently plot them. I wonder if anybody can offer any help on this topic? Below I applied the lda function on a small dataset of mine. Any help will be much appreciated. > library(MASS) >

If I have two vectors X<-1:10 Y<-1:5 When I combine them using cbind, the shorter one is repeated and both are made of the same length. Is there a methods that does this without duplicating the shorter one. I want to use this to store the data back to a file. Thanks ../Murli [[alternative HTML version deleted]]

If my sample size is small is there a particular switch option that I need to use with t.test so that it calculates the t ratio correctly? Here is a dummy example? á =0.05 Mean pain reduction for A =27; B =31 and SD are SDA=9 SDB=12 drgA.p<-rnorm(5,27,9); drgB.p<-rnorm(5,31,12) t.test(drgA.p,drgB.p) # what do I need to give as additional parameter here? I can do it manually but

If I have a calculated t can I get the probability associated with it using an R function by giving it the df and t? I know I can do the whole calculation using t.test() or get the t-distribution using qt(). If t=1.11 and df =9 can I get the probability? Thanks../Murli [[alternative HTML version deleted]]

Is there a function that calculates the inter-rater agreement index (kappa) in R? Thanks ../Murli [[alternative HTML version deleted]]

I am trying to sample a subset from a matrix using sample. The size of the matrix is 20X 1532. It works fine with this, but when I transpose the matrix and try to sample it, it returns null. pick.set<-sample(tissue.exp.t,5,replace=FALSE,prob=NULL) Is there something that I am missing here ? Thanks ../Murli

Hi !! Is there a good tutorial for the R language ? I really find it hard to find methods in R. Thanks and Cheers ../Murli

I am trying to calculate coordinate transformations and in the process of debugging my code using debug I found the following Browse[1]> direction[i] [1] -1.570796 Browse[1]> cos(direction[i]) [1] 6.123032e-17 Browse[1]> cos(-1.570796) [1] 3.267949e-07 Browse[1]> direction[i] [1] -1.570796 Browse[1]> cos(direction[i]) [1] 6.123032e-17 Browse[1]> cos(-1.570796) [1] 3.267949e-07

Hi there, I am a master student in Denmark, and apply R to analyze the drug data. I use the function 'lda' to obtain a linear discriminant object, and then wish to use 'plot.lda' to do the plot on this object like below. drug.lda <- lda(Inhibition ~ NET_CHARGE + PKA_1 + MW + MLOGP, data = drug.class, method = "moment") plot.lda(drug.lda,

> > library(MASS) > Iris <- data.frame(rbind(iris3[,,1], iris3[,,2], iris3[,,3]), + Sp = rep(c("s","c","v"), rep(50,3))) > train <- sample(1:150, 75) > table(Iris$Sp[train]) c s v 22 23 30 > z <- lda(Sp ~ ., Iris, prior = c(1,1,1)/3, subset = train) Error in if (targetlist[i] == stringname) { : argument is of length

Which is the parameter that is used to decrease the size of ylabs plotted in biplot? I tried playing with cex and cex.lab I am not getting it right pc <- princomp(USArrests) biplot(pc, xlabs = rep("", nrow(USArrests)),ylabs=(colnames(USArrests))) Thanks../Murli [[alternative HTML version deleted]]

I used the multcomp package sometime back for doing multiple comparisons. I see that it has been updated and the methods like simint are no longer supported. When I run the program it prompts to me to use glht. How do I get the lower and upper conf int and the pValues using glht? Does anyone have an example? Thanks ../Murli [[alternative HTML version deleted]]

Can I insert an element in an array at a particular position without destroying the already existing element? X<-c(1,2,3,4,5) I want to insert an element between 1 and 2. Thanks ../Murli [[alternative HTML version deleted]]

Hi!! I am interesting in computing the radius of an arc that best approximates a curve. Is there an R function that I can use to draw an arc? Nothing useful came up when I searched help.search. Does anyone have any suggestion to do this? Thanks ../Murli

I am trying split a string and use one part of it to label graphs. I am using strsplit for that. While I am able to split it, how do I access the separated parts. > filName<-"chrI_2223" >part<- strsplit(filName,"\\_") > part [[1]] [1] "chrI" "2223" > part[1] [[1]] [1] "chrI" "2223" I looked up the help archive but did

Dear all, can anybody help me with the program below? The function predict.lda seems to be defined but cannot be used by errortest. The R version is 1.7.1 Thanks in advance, Stefan ---------------- library("MASS"); library("ipred"); data(iris3); tr <- sample(1:50, 25); train <- rbind(iris3[tr,,1], iris3[tr,,2], iris3[tr,,3]); test <- rbind(iris3[-tr,,1],

Hello everyone, I am working on a linear discriminant analysis and am having issues finding the full output of my lda. Specifically, there is no reporting of the Proportion of Trace that is a normal output of the procedure. I'm using a csv file and everything is reading in correctly. I've looked and looked and can't figure out why my output is not complete. Is it something simple that

Is there an option to draw concentration ellipses in biplots ? It seems really nice to summarize large number of points of each group. Cheers../ Murli

Here it is again, hope this is more clear I am using the following data (only a small subset is given): Habitat Fungus.yield Birch 20.83829053 Birch 22.9718181 Birch 22.28216829 Birch 24.23136797 Birch 22.32147961 Birch 20.30783598 Oak 27.24047258 Oak 29.7730014 Oak 30.12608508 Oak 25.76088669 Oak 30.14750974 Hornbeam 17.05307949 Hornbeam 15.32805111 Hornbeam 18.26920177 Hornbeam 21.30987049