FLXnested-class.RdSpecification of nesting structure for regression coefficients.
Objects can be created by calls of the form new("FLXnested",
formula, k, ...). In addition, named lists can be coerced to
FLXnested objects, names are completed if unique.
formula:Object of class "list" containing the
formula for determining the model matrix for each nested parameter.
k:Object of class "numeric" specifying the
number of components in each group.