plsca: PLS-CA: Partial Least Squares Canonical Analysis
Description
Performs partial least squares canonical analysis for two blocks of data. Compared to PLSR2, the blocks of variables in PLS-CA play a symmetric role (i.e. there is neither predictors nor predictands)
Usage
plsca(X, Y, nc = NULL, scaled = TRUE)
Arguments
X
A numeric matrix or data frame (X-block).
Y
A numeric matrix or data frame (Y-block).
nc
The number of extracted PLS components (NULL by default)
scaled
A logical value indicating whether scaling data should be performed (TRUE by default).
Value
An object of class "plsca", basically a list with the following elements:
x.scoresscores of the X-block (also referred to as T components).
x.wgsweights of the X-block.
x.loadsloadings of the X-block.
y.scoresscores of the Y-block (also referred to as U components).
y.wgsweights of the Y-block.
y.loadsloadings of the Y-block.
cor.xtcorrelations between X and T.
cor.yucorrelations between Y and U.
cor.tucorrelations between T and U.
cor.xucorrelations between X and U.
cor.ytcorrelations between Y and T.
R2Xexplained variance of X by T.
R2Yexplained variance of Y by U.
com.xucommunality of X with U.
com.ytcommunality of Y with T.
Details
Arguments X and Y must contain more than one variable.
No missing data are allowed.
When nc=NULL the number of components is determined by taking the minimum between the number of columns from X and Y.
When scaled=TRUE the data is scaled to standardized values (mean=0, variance=1). Otherwise the data will only be centered (mean=0).
References
Tenenhaus, M. (1998) La Regression PLS. Theorie et Pratique. Editions TECHNIP, Paris.