asv.asreml computes the approximate stratum variances, degrees of freedom and coefficients for simple variance component models.
## S3 method for class 'asreml' asv(object, order = c("as.is", "noeff"), vvp = FALSE, ...)
||An object of class
||The sequence in which to consider the random terms: may be one of “
|…||Any additional arguments.|
Approximate stratum variances and degrees of freedom for simple variance components models are returned. For the linear mixed-effects model, it is often possible to consider a natural ordering of the variance component parameters, including the residual. Based on an idea due to Thompson, 1980,
asreml computes approximate stratum degrees of freedom and stratum variances by a modified Cholesky diagonalisation of the average information matrix.
FALSE, a rectangular matrix containing the degrees of freedom, approximate variances and the component coefficients for each random term. If
TRUE, a list of length two containing the matrix of approximate stratum variances and the inverse average information matrix of the variance components in list components
Thompson R (1980). “Maximum likelihood estimation of variance components.” Series Statistics, 11(4), pp. 545-561.