nas: Net Analyte Signal

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

Net Analyte Signal

Description

This function implements the Net Analyte Signal (NAS) algorithm, as proposed by Lorber (1997), which involves the concentration matrix. NAS aims to remove information from the predictor variables, that is orthogonal or irrelevant to the response variable(s) by orthogonal projection.

Usage

nas(x, y, ncomp = 5, center = TRUE, scale = FALSE)

Arguments

x	A matrix or data frame of the predictor variables
y	A vector, matrix or data frame of the response variable(s)
ncomp	An integer specifying the number of principal components to retain for orthogonal processing. Default is 5.
center	A logical value specifying whether to center the data. Default is TRUE.
scale	A logical value specifying whether to scale the data. Default is FALSE.

Details

The NAS algorithm aims to obtain a corrected matrix that contains only the information relevant to the response variable \textbf{Y}. This is achieved by constructing an orthogonal projection matrix based on the principal components of the data matrix, \textbf{X}, that are orthogonal to \textbf{Y}. The corrected matrix is then obtained by projecting \textbf{X} onto the subspace orthogonal to the unwanted components.

Value

A tibble containing the corrected predictor variables

Author(s)

Christian L. Goueguel

References

• Lorber, A., (1997). Net analyte signal calculation in multivariate calibration. Anal. Chem., 69(8):1620-1626

• Faber, N.M., (1998). Efficient computation of net analyte signal vector in inverse multivariate calibration models. Anal. Chem., 70(23):5108-5110

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