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CompositionalSR (version 1.0)

Marginal effects for the alpha-SLX model: Marginal effects for the \(\alpha\)-SLX model

Description

Marginal effects for the \(\alpha\)-SLX model.

Usage

me.aslx(be, gama, mu, x, coords, k = 10, cov_theta = NULL)

Value

A list including:

me.dir

An array with the direct marginal effects of each component for each predictor variable.

me.indir

An array with the indirect marginal effects of each component for each predictor variable.

me.total

An array with the total marginal effects of each component for each predictor variable.

ame.dir

An array with the average direct marginal effects of each component for each predictor variable.

ame.indir

An array with the average indirect marginal effects of each component for each predictor variable.

ame.total

An array with the aerage total marginal effects of each component for each predictor variable.

se.amedir

An array with the standard errors of the average direct marginal effects of each component for each predictor variable. This is returned if you supply the covariance matrix cov_theta.

se.ameindir

An array with the standard errors of the average indirect marginal effects of each component for each predictor variable. This is returned if you supply the covariance matrix cov_theta.

se.ametotal

An array with the standard errors of the average total marginal effects of each component for each predictor variable. This is returned if you supply the covariance matrix cov_theta.

Arguments

be

A matrix with the beta coefficients of the \(\alpha\)-SLX model.

gama

A matrix with the gamma coefficients of the \(\alpha\)-SLX model.

mu

The fitted values of the \(\alpha\)-SLX model.

x

A matrix with the continuous predictor variables or a data frame. Categorical predictor variables are not suited here.

coords

A matrix with the coordinates of the locations. The first column is the latitude and the second is the longitude.

k

The number of nearest neighbours to consider for the contiguity matrix.

cov_theta

The covariance matrix of the beta and gamma regression coefficients. If you pass this argument, then the standard error of the average marginal effects will be returned.

Author

Michail Tsagris.

R implementation and documentation: Michail Tsagris mtsagris@uoc.gr.

Details

The \(\alpha\)-transformation is applied to the compositional data first and then the \(\alpha\)-SLX model is applied.

References

Tsagris M. (2025). The \(\alpha\)--regression for compositional data: a unified framework for standard, spatially-lagged, and geographically-weighted regression models. https://arxiv.org/pdf/2510.12663

Tsagris M. (2015). Regression analysis with compositional data containing zero values. Chilean Journal of Statistics, 6(2): 47-57. https://arxiv.org/pdf/1508.01913v1.pdf

Tsagris M.T., Preston S. and Wood A.T.A. (2011). A data-based power transformation for compositional data. In Proceedings of the 4th Compositional Data Analysis Workshop, Girona, Spain. https://arxiv.org/pdf/1106.1451.pdf

See Also

me.gwar, me.ar, alfa.slx

Examples

Run this code
data(fadn)
coords <- fadn[, 1:2]
y <- fadn[, 3:7]
x <- fadn[, 8]
mod <- alfa.slx(y, x, a = 0.5, coords, k = 10, xnew = x, coordsnew = coords)
me <- me.aslx(mod$be, mod$gama, mod$est, x, coords, k = 10)

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