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Question about PLS regression

3 messages · Andris Jankevics, Bjørn-Helge Mevik

#
Hello useRs,

I am new user to R and also statistics. Why predicted results in this example 
are different? Is the order of variables in X matrix important?

library (pls)
set.seed (1)
Y1 <- c(1,2,3,4,5,6,7,8,9,10)
Y2 <- c(0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1.0)
X1 <- rnorm(10,sd=0.2)
X2 <- rnorm(10,sd=1)
X3 <- rnorm(10,sd=0.1)
X4 <- rnorm(10,sd=0.1)
X5 <- rnorm(10,sd=0.1)

KAL <- data.frame(num=c(1:10))
KAL$Y <- as.matrix(cbind (Y1,Y2))
KAL$X <- as.matrix(cbind (X1,X2,X3,X4,X5))
KAL2 <- data.frame(num=c(1:10))
KAL2$Y <- as.matrix(cbind (Y1,Y2))
KAL2$X <- as.matrix(cbind (X5,X4,X3,X2,X1))

PLS <- plsr (Y~X,data=KAL, 4,validation = "CV")
PLS2 <- plsr (Y~X,data=KAL2,4, validation = "CV")

X1v <- rnorm(10,sd=0.1)
X2v <- rnorm(10,sd=1)
X3v <- rnorm(10,sd=0.1)
X4v <- rnorm(10,sd=0.1)
X5v <- rnorm(10,sd=0.1)
VAL <- data.frame(num=c(1:10))
VAL$X <- as.matrix(cbind(X1v,X2v,X3v,X4v,X5v))

predict (PLS,VAL,4)
predict (PLS2,VAL,4)	

Thank You,

Andris Jankevics
#
I am sorry. It was my fault. My example is wrong. I need also rearrange a 
validation data set too.
But I have a sligthy different results with my real data. Where can the 
problem be?

Andris Jankevics
On Otrdiena, 18. Apr?lis 2006 17:55, Andris Jankevics wrote:
#
Andris Jankevics wrote:

            
I think you have to supply some details for anyone to be able to
answer.  At least what you did (the code), what you got (the results)
and what you expected to get.