ABSTRACT
The expansion method is a procedure that involves the construction of complex terminal models from simple initial models. It is a valuable research tool from at least three perspectives. First, it forces the researcher to question the usually implicit assumption of parameter stability inherent in most models and empirical analyses. Second, the expansion method formalizes the exploration of various types of parameter change, or drift, along such relevant dimensions as time or distance. Discovery of drift in these cases may lead to refinement of existing theory or to the formation of new constructs to account for the identified patterns. Third, the method allows for the derivation of specific models that can be used in rigorous hypothesis-testing frameworks aimed at determining the validity of competing theoretical propositions.
