The Cowles Foundation for Research in Economics (Yale University, established 1955 as the successor to the Cowles Commission — Colorado Springs, then Chicago, 1932–1955) is the institutional home of the Cowles Commission methodology: the structural, simultaneous-equations approach that defined mid-twentieth-century econometrics. Its researchers (Haavelmo, Koopmans, Klein, Marschak, and others) formalized the probabilistic foundations of econometrics, the identification of simultaneous-equations systems, and the estimators used to recover structural parameters from non-experimental economic data.
The Cowles programme established the methodological template — specify a structural economic model, identify it, estimate its parameters, then use it for policy analysis and forecasting — against which modern alternatives define themselves. Sims's (1980) VAR critique, the LSE general-to-specific approach, and the DSGE research programme are all responses to the Cowles structural paradigm. Ray C. Fair's large-scale macroeconometric model and stochastic-simulation framework were developed in affiliation with the Foundation (Fair 1980).