param_obj is the abstract base S7 class for all population parameter
objects, analogous to var_id(). Concrete subclasses (MU, PI,RHO)
inherit from it. The base class is a pure marker — each
subclass declares its own properties.
param_obj is the abstract base S7 class for all population parameter
objects, analogous to var_id(). Concrete subclasses (MU, PI,RHO)
inherit from it. The base class is a pure marker — each
subclass declares its own properties.