This can be used to reduce the amount of workspace used by `REML`

when the Fisher scoring method is used (i.e. when the `METHOD`

option of `REML`

is set to Fisher). It is defined by the `VCOMPONENTS`

directive, and can be taken from either the fixed or the random model. `REML`

uses the factor to divide the model terms into two groups; this partition is then used in calculations during the fitting process to reduce the size of the matrices that have to be inverted and stored. Use of an absorbing factor can thus save computing time and data space. However, although exactly the same model is fitted when an absorbing factor is used, standard errors are unavailable for some model terms.

# Absorbing factor

Updated on December 4, 2017