Path: Janda's Home Page > Workshop > Canonical Analysis > Outline

When is canonical analysis appropriate?

 

  • Canonical analysis computes weights for two sets of variables, A and B, such that it maximizes the simple product moment correlation between the weighted composite scores for set A and set B.
    • The canonical correlation is interpreted exactly as a simple product-moment correlation.
    • The weights on both sides of the equation (canonical variates) are analogous to b-coefficients in linear regression.
    • More than one canonical correlation is produced for each analysis.
      • The number of canonical correlations (roots) equals the larger of the two sets of variables.
      • The first canonical correlation is the largest; successive ones are progressively smaller.
      • Scores produced from canonical variates are unrelated across roots.
  • Whereas factor analysis can be used appropriately as a tool for exploratory research, canonical analysis needs to be guided by theory.
  • Canonical analysis is a tool for testing theory; not developing measures.
    • Alternative measures of the same concept should not be included in a canonical variate.
    • Instead, combine the measures to form a scale, compute its reliability, and use the scale in analysis.
  • Consider canonical analysis for relating variables grouped under "umbrella concepts."
    • Umbrella concepts group together variables that share some conceptual underpinnings but that express distinct phenomena.
    • Consequently, the concepts are not closely related--in the sense of unidemensionality.
    • Some examples of umbrella concepts:
      • International relations, which embraces
        • war and peace
        • armed conflicts
        • economic trade
        • and so on.
      • Congressional behavior, which embraces
        • party unity in congressional voting
        • introduction of bills
        • committee participation
      • Political party organization
        • centralization of power
        • structural complexity
      • Political party performance
        • winning elections
        • providing services for members