R: Orthogonal scores PLSR

oscorespls.fit {pls} | R Documentation

## Orthogonal scores PLSR

### Description

Fits a PLSR model with the orthogonal scores algorithm (aka the NIPALS algorithm).

### Usage

    oscorespls.fit(X, Y, ncomp, center = TRUE, stripped = FALSE,
                   tol = .Machine$double.eps^0.5, maxit = 100, ...)

### Arguments

`X` | a matrix of observations. `NA`s and `Inf`s are not allowed.
`Y` | a vector or matrix of responses. `NA`s and `Inf`s are not allowed.
`ncomp` | the number of components to be used in the modelling.
`center` | logical, determines if the X and Y matrices are mean centered or not. Default is to perform mean centering.
`stripped` | logical. If `TRUE` the calculations are stripped as much as possible for speed; this is meant for use with cross-validation or simulations when only the coefficients are needed. Defaults to `FALSE`.
`tol` | numeric. The tolerance used for determining convergence in multi-response models.
`maxit` | positive integer. The maximal number of iterations used in the internal Eigenvector calculation.
`...` | other arguments. Currently ignored.

### Details

This function should not be called directly, but through the generic functions `plsr` or `mvr` with the argument `method="oscorespls"`. It implements the orthogonal scores algorithm, as described in Martens and Næs (1989). This is one of the two “classical” PLSR algorithms, the other being the orthogonal loadings algorithm.

### Value

A list containing the following components is returned:

`coefficients` | an array of regression coefficients for 1, ..., `ncomp` components. The dimensions of `coefficients` are `c(nvar, npred, ncomp)` with `nvar` the number of `X` variables and `npred` the number of variables to be predicted in `Y`.
`scores` | a matrix of scores.
`loadings` | a matrix of loadings.
`loading.weights` | a matrix of loading weights.
`Yscores` | a matrix of Y-scores.
`Yloadings` | a matrix of Y-loadings.
`projection` | the projection matrix used to convert X to scores.
`Xmeans` | a vector of means of the X variables.
`Ymeans` | a vector of means of the Y variables.
`fitted.values` | an array of fitted values. The dimensions of `fitted.values` are `c(nobj, npred, ncomp)` with `nobj` the number samples and `npred` the number of Y variables.
`residuals` | an array of regression residuals. It has the same dimensions as `fitted.values`.
`Xvar` | a vector with the amount of X-variance explained by each component.
`Xtotvar` | Total variance in `X`.

If `stripped` is `TRUE`, only the components `coefficients`, `Xmeans` and `Ymeans` are returned.

### Author(s)

Ron Wehrens and Bjørn-Helge Mevik

### References

Martens, H., Næs, T. (1989) Multivariate calibration. Chichester: Wiley.

### See Also

`mvr` `plsr` `pcr` `kernelpls.fit` `widekernelpls.fit` `simpls.fit`

[Package pls version 2.7-0 Index]