Creates an ARMA matrix of order one with parameters specified.
Usage
ARMA(x, rho=0.25, lambda=0.25)
Value
If everything is defined correctly the function returns:
$nn
the correlation matrix
Arguments
x
vector of the variable to define the factor levels for the ARMA covariance structure.
rho
rho value for the matrix.
lambda
dimensions of the square matrix.
Details
Specially useful for constructing covariance structures for rows and ranges to capture better the spatial variation trends in the field. The rho value is assumed fixed and values of the variance component will be optimized through REML.
References
Covarrubias-Pazaran G (2016) Genome assisted prediction of quantitative traits using the R package sommer. PLoS ONE 11(6): doi:10.1371/journal.pone.0156744