opls: Orthogonal Projections to Latent Structures

In ChristianGoueguel/specProc: Preprocessing Tools For Laser-Induced Breakdown Spectroscopy (LIBS) Spectra

Orthogonal Projections to Latent Structures

Description

This function fits an Orthogonal Projections to Latent Structures (OPLS) model to the provided x (predictor) and y (response) data.

Usage

opls(x, y, scale = "center", crossval = 7, permutation = 20)

Arguments

x	A data.frame or tibble containing the x-data (predictors).
y	A data.frame or tibble containing the y-data (responses).
scale	A character string indicating the scaling method for the data ("center" or "pareto").
crossval	An integer representing the number of cross-validation groups.
permutation	An integer representing the number of permutations for the permutation test.

Details

OPLS is a supervised modeling technique used to find the multidimensional direction in the x-space that explains the maximum multidimensional variance in the y-space. It separates the systematic variation in x into two parts: one that is linearly related to y (predictive components) and one that is statistically uncorrelated to the response variable y (orthogonal components).

Value

A list containing the following components:

x_scores

A matrix of x-scores (the projections of the x-data onto the predictive components).

x_loadings

A matrix of x-loadings (the weights of the original x-variables on the predictive components).

x_weights

A matrix of x-weights (the weights used to calculate the x-scores).

orthoScores

A matrix of orthogonal scores (the projections of the x-data onto the orthogonal components).

orthoLoadings

A matrix of orthogonal loadings (the weights of the original x-variables on the orthogonal components).

orthoWeights

A matrix of orthogonal weights (the weights used to calculate the orthogonal scores).

y_weights

A matrix of y-weights (the weights used to calculate the y-scores).

y_orthoWeights

A matrix of orthogonal y-weights (the weights used to calculate the orthogonal y-scores).

y_scores

A matrix of y-scores (the projections of the y-data onto the predictive components).

Author(s)

Christian L. Goueguel

References

• Trygg, J., and Wold, S., (2002). Orthogonal projections to latent structures (O-PLS). Journal of Chemometrics, 16(3):119-128.

ChristianGoueguel/specProc documentation built on Nov. 9, 2024, 3:23 p.m.