R is a dimensionless value between 0 and 1. In principle its value
determines themagnitude of change inMinduced by a change in any xij.
However as the final Ms is scaled with the M's of the random situations
with the same R, the actual value of the R contributes only slightly on the
final result. However, in order to keep all themixing values comparable
with each other the value for R must be chosen systematically.