I'm trying to reduce highly dimensional data with factor methods. I'm using Principal component analysis and Partial least squares.
From these methods I'm using the first component as a Common factor to summarize the data.
Is it possible that PCA and PLS produce wildly different first components with the same initial data? Or is the R code wrong?
Figure 1: The first Principal component
Figure 2: The first PLS component
These figures imply that first components have pretty different kind of trend. Is this normal that first components are so different between the PCA and PLS?
My code for the PLS and PCA were:
model_pls <- plsr(y ~ as.matrix(X), data = ddata)
#excluding the y variable
newddata <- ddata[2:19]
model_pca <- prcomp(newddata, scale =TRUE)
first_comp_pca <- model_pca$x[,1]
Thank you for advance!