VarCorr: Extract variance and correlation components
Description
This function calculates the estimated variances, standard
deviations, and correlations between the random-effects terms in a
linear mixed-effects model, of class lme, or a nonlinear
mixed-effects model, of class nlme. The within-group error
variance and standard deviation are also calculated.
Usage
VarCorr(x, sigma, rdig)
Arguments
Value
a matrix with the estimated variances, standard deviations, and
correlations for the random effects. The first two columns, named
Variance and StdDev, give, respectively, the variance
and the standard deviations. If there are correlation components in
the random effects model, the third column, named Corr,
and the remaining unnamed columns give the estimated correlations
among random effects within the same level of grouping. The
within-group error variance and standard deviation are included as
the last row in the matrix.
References
Pinheiro, J.C., and Bates, D.M. (2000) "Mixed-Effects Models
in S and S-PLUS", Springer, esp. pp. 100, 461.