Many scholars define theory in terms of relationships
between independent and dependent variables.
For example, Campbell defined theory as “a
collection of assertions, both verbal and symbolic,
that identifies what variables are important and for
what reasons, specifies how they are interrelated
and why, and identifies the conditions under
which they should be related or not related” (1990:
65). From this perspective, a theory is evaluated
primarily by its ability to explain variance in a
criterion of interest (Bacharach, 1989). Other scholars
have defined theory in terms of narratives and
accounts. For example, DiMaggio defined theory as