set
can be 1) a vector or 2) a right-hand sided formula in which
variables are separated by '+'. In either case, it is tested if the first
two variables in the set
are conditionally independent given the
remaining variables in set
. (Notice an abuse of the '+' operator in
the right-hand sided formula: The order of the variables does matter.)
If set
is NULL
then it is tested whether the first two
variables are conditionally independent given the remaining variables.
x
must be a list with components cov
and n.obs
such as
returned by calling cov.wt( , method='ML')
on a dataframe.