MINC attempts to provide some level of data organization through a
hierarchy of group variables. As mentioned above, attributes are
grouped according to type in group variables. Each group variable can
have an MIparent and an MIchildren attribute -- the
former specifying the name of another variable that is above this one
in the hierarchy, the latter specifying a newline-separated list of
variables that come below this one in the hierarchy. At the root of
the hierarchy is the MIrootvariable variable, with no parent.
Although it is not necessary to make use of this structure, it can
provide a mechanism for ordering large amounts of information.