- An
empirical theory consists of
- concepts
(generalized ideas that embrace instances of reality)
- linked
together in a set of causal
relations.
- Hence,
a theory is an interrelated set of empirical
statements
- that
can be tested by observing instances of reality that
underlie the concepts.
- Abstract
concepts must be clearly defined.
- Consider
the conceptual definition of
party identification
- --defined
as a "psychological preference for a
party,"
- --it
refers to attitudes, not behavior.
- Identifying
with a party is not the same as voting for
that party's candidates.
- Hence,
the following statement is testable, not
tautological:
- Citizens
who identify with a party tend to vote for
that party's candidates.
- Sometimes,
the fit between theoretical concept and observable
reality is direct and nonproblematic:
- Voting
for a party's candidates can be equated with reports
of voting decisions.
- Usually,
the fit is indirect and problematic:
- We
don't observe the concepts, we observe "stand-ins" for
the concepts, called
- Observables
are equated with concepts through a process called
operationalization
- Often,
a set of operations are needed to measure a
concept.
- Consider
the operational definition of party
identification
- "The
issue of whether or not there is any correspondence
between our concepts and variables on the one hand and
our indicators or measure on the other is the central
problem of measurement in science." (Manheim and Rich
(1991), p. 58)
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