“…That is, given the loss function (4), the true data generating process is determined by commitment to a simply policy rule whose coefficients are chosen to minimize expected loss. If instead we assumed that policy is the outcome of optimal commitment (e.g., Ilbas, 2007) or optimal discretion (e.g., Dennis, 2004;So¨derlind et al, 2005), then we could still preserve the GMM framework by augmenting the system with appropriate first-order conditions from the Lagrangian as shown by So¨derlind (1999). Taking that step here, however, would amount to imposing false restrictions on the model given our assumption about the nature of policy.…”