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Theory and Concepts / Operationalization and Measurement
  • 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
      • variables, or
      • indicators
    • Observables are equated with concepts through a process called operationalization
  • "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)