Spurious Correlation: A Causal Interpretation*
Abstract * I am indebted to Richard M. Cyert, Paul F. Lazarsfeld, Roy Radner, and T. C Koopmans for valuable comments on earlier drafts of this paper. To test whether a correlation between two variables is genuine or spurious, additional variables and equations must be introduced, and sufficient assumptions must be made to identify the parameters of this wider system. If the two original variables are causally related in the wider system, the correlation is “genuine.”