VCA (version 1.5.1)

lmerG: Construct Variance-Covariance Matrix of Random Effects for Models Fitted by Function 'lmer'

Description

This function restricts the variance-covariance matrix of random effects \(G\) to be either diagonal ('cov=FALSE') or to take any non-zero covariances into account (default, 'cov=TRUE').

Usage

lmerG(obj, cov = FALSE)

Value

(Matrix) representing the variance-covariance structure of random effects \(G\)

Arguments

obj

(object) inheriting from class 'lmerMod'

cov

(logical) TRUE = in case of non-zero covariances a block diagonal matrix will be constructed, FALSE = a diagonal matrix with all off-diagonal element being equal to zero will be contructed

Author

Andre Schuetzenmeister

Details

This function is not intended to be called directly by users and therefore not exported!

Examples

if (FALSE) {
library(lme4)
data(Orthodont)
Ortho <- Orthodont
Ortho$age2 <- Ortho$age - 11
Ortho$Subject <- factor(as.character(Ortho$Subject))
fit <-lmer(distance~Sex+Sex:age2+(age2|Subject), Ortho) 
G1 <- VCA:::lmerG(fit, cov=FALSE)
G2 <- VCA:::lmerG(fit, cov=TRUE)
G1[1:10,1:10]
G2[1:10,1:10]
}