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Robustifying Learnability

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  • Peter von zur Muehlen
  • Robert J. Tetlow

Abstract

In recent years, the learnability of rational expectations equilibria (REE) and determinacy of economic structures have rightfully joined the usual performance criteria among the sought after goals of policy design. And while some contributions to the literature (for example Bullard and Mitra (2001) and Evans and Honkapohja (2002)) have made significant headway in establishing certain features of monetary policy rules that facilitate learning, a comprehensive treatment of policy design for learnability has yet to surface, especially for cases in which agents have potentially misspecified their learning models. This paper provides such a treatment. We argue that since even among professional economists a generally acceptable workhorse model of the economy has not been agreed upon, it is unreasonable to expect private agents to have collective rational expectations. We assume instead that agents have an approximate understanding of the workings of the economy and that their task of learning true reduced forms of the economy is subject to potentially destabilizing errors. We then ask: can a central bank set policy that accounts for learning errors but also succeeds in bounding them in a way that allows eventual learnability of the model, given policy. For different parameterizations of a given policy rule applied to a New Keynesian model, we use structured singular value analysis (from robust control) to find the largest ranges of misspecifications that can be tolerated in a learning model without compromising convergence to an REE. A parallel set of experiments seeks to determine the optimal stance (strong inflation as opposed to strong output stabilization) that allows for the greatest scope of errors in learning without leading to expectational instabilty in cases when the central bank designs both optimal and robust policy rules with commitment. We compare the features of all the rules contemplated in the paper with those that maximize economic performance in the true model, and we measure the performance cost of maximizing learnability under the various conditions mentioned here.

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Bibliographic Info

Paper provided by Society for Computational Economics in its series Computing in Economics and Finance 2005 with number 437.

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Date of creation: 11 Nov 2005
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Handle: RePEc:sce:scecf5:437

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Keywords: monetary policy; learning; E-stability; model uncertainty; robustness;

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  1. Andrew Levin & Volker Wieland & John C. Williams, 1998. "Robustness of simple monetary policy rules under model uncertainty," Finance and Economics Discussion Series 1998-45, Board of Governors of the Federal Reserve System (U.S.).
  2. Seppo Honkapohja & Kaushik Mitra, 2002. "Learning Stability in Economies with Heterogenous Agents," CESifo Working Paper Series 772, CESifo Group Munich.
  3. Marcet, Albert & Sargent, Thomas J., 1989. "Convergence of least squares learning mechanisms in self-referential linear stochastic models," Journal of Economic Theory, Elsevier, vol. 48(2), pages 337-368, August.
  4. Rogoff, Kenneth, 1985. "The Optimal Degree of Commitment to an Intermediate Monetary Target," The Quarterly Journal of Economics, MIT Press, vol. 100(4), pages 1169-89, November.
  5. Michael Woodford, 2003. "Optimal Interest-Rate Smoothing," Review of Economic Studies, Wiley Blackwell, vol. 70(4), pages 861-886, October.
  6. Bennett T. McCallum, 1981. "On Non-Uniqueness in Rational Expectations Models: An Attempt at Perspective," NBER Working Papers 0684, National Bureau of Economic Research, Inc.
  7. Woodford, M., 1999. "Optimal Monetary Policy Inertia.," Papers 666, Stockholm - International Economic Studies.
  8. James Bullard & Kaushik Mitra, 2003. "Determinacy, learnability, and monetary policy inertia," Working Papers 2000-030, Federal Reserve Bank of St. Louis.
  9. Lubik, Thomas A. & Schorfheide, Frank, 2003. "Computing sunspot equilibria in linear rational expectations models," Journal of Economic Dynamics and Control, Elsevier, vol. 28(2), pages 273-285, November.
  10. Albert Marcet & Juan P. Nicolini, 2003. "Recurrent Hyperinflations and Learning," American Economic Review, American Economic Association, vol. 93(5), pages 1476-1498, December.
  11. Athanasios Orphanides & Richard D. Porter & David Reifschneider & Robert Tetlow & Frederico Finan, 1999. "Errors in the measurement of the output gap and the design of monetary policy," Finance and Economics Discussion Series 1999-45, Board of Governors of the Federal Reserve System (U.S.).
  12. Giordani, Paolo & Söderlind, Paul, 2002. "Solution of Macromodels with Hansen-Sargent Robust Policies: Some Extensions," Working Paper Series in Economics and Finance 499, Stockholm School of Economics, revised 15 May 2003.
  13. George W. Evans & Seppo Honkapohja, 2004. "Adaptive learning and monetary policy design," Macroeconomics 0405008, EconWPA.
  14. Evans, G.W. & Honkapohja ,S. & Williams, N., 2005. "Generalized Stochastic Gradient Learning," Cambridge Working Papers in Economics 0545, Faculty of Economics, University of Cambridge.
  15. James Bullard & Stefano Eusepi, 2003. "Did the Great Inflation occur despite policymaker commitment to a Taylor rule?," Working Paper 2003-20, Federal Reserve Bank of Atlanta.
  16. Ben S. Bernanke & Julio J. Rotemberg, 1997. "NBER Macroeconomics Annual 1997, Volume 12," NBER Books, National Bureau of Economic Research, Inc, number bern97-1, July.
  17. Evans, George W. & McGough, Bruce, 2003. "Monetary policy, indeterminacy and learning," CFS Working Paper Series 2003/37, Center for Financial Studies (CFS).
  18. George W. Evans & Seppo Honkapohja, 2002. "Monetary Policy, Expectations and Commitment," University of Oregon Economics Department Working Papers 2002-11, University of Oregon Economics Department, revised 01 Feb 2004.
  19. Blanchard, Olivier Jean & Kahn, Charles M, 1980. "The Solution of Linear Difference Models under Rational Expectations," Econometrica, Econometric Society, vol. 48(5), pages 1305-11, July.
  20. Levin, Andrew & Wieland, Volker & Williams, John C., 2003. "The performance of forecast-based monetary policy rules under model uncertainty," CFS Working Paper Series 2003/06, Center for Financial Studies (CFS).
  21. Walsh, Carl E., 2005. "Parameter misspecification and robust monetary policy rules," Working Paper Series 0477, European Central Bank.
  22. Coenen, Günter, 2003. "Inflation persistence and robust monetary policy design," Working Paper Series 0290, European Central Bank.
  23. Taylor, John B., 1993. "Discretion versus policy rules in practice," Carnegie-Rochester Conference Series on Public Policy, Elsevier, vol. 39(1), pages 195-214, December.
  24. Garratt, Anthony & Hall, Stephen G., 1997. "E-equilibria and adaptive expectations: Output and inflation in the LBS model," Journal of Economic Dynamics and Control, Elsevier, vol. 21(7), pages 1149-1171, June.
  25. Kaushik Mitra & James Bullard, . "Learning About Monetary Policy Rules," Discussion Papers 00/41, Department of Economics, University of York.
  26. George W. Evans & Seppo Honkapohja, 2003. "Expectations and the Stability Problem for Optimal Monetary Policies," Review of Economic Studies, Oxford University Press, vol. 70(4), pages 807-824.
  27. Thomas A. Lubik & Frank Schorfheide, 2004. "Testing for Indeterminacy: An Application to U.S. Monetary Policy," American Economic Review, American Economic Association, vol. 94(1), pages 190-217, March.
  28. Robert J. Tetlow & Peter von zur Muehlen, 2000. "Robust monetary policy with misspecified models: does model uncertainty always call for attenuated policy?," Finance and Economics Discussion Series 2000-28, Board of Governors of the Federal Reserve System (U.S.).
  29. Robert J. Tetlow & Peter von zur Muehlen, 2002. "Avoiding Nash inflation: Bayesian and robust responses to model uncertainty," Finance and Economics Discussion Series 2002-9, Board of Governors of the Federal Reserve System (U.S.).
  30. Bruce McGough & George Evans, 2004. "Optimal Constrained Interest Rate Rules," Computing in Economics and Finance 2004 134, Society for Computational Economics.
  31. Bernanke, Ben S & Woodford, Michael, 1997. "Inflation Forecasts and Monetary Policy," Journal of Money, Credit and Banking, Blackwell Publishing, vol. 29(4), pages 653-84, November.
  32. Julio Rotemberg & Michael Woodford, 1997. "An Optimization-Based Econometric Framework for the Evaluation of Monetary Policy," NBER Chapters, in: NBER Macroeconomics Annual 1997, Volume 12, pages 297-361 National Bureau of Economic Research, Inc.
  33. Alexei Onatski & James H. Stock, 1999. "Robust monetary policy under model uncertainty in a small model of the U.S. economy," Proceedings, Federal Reserve Bank of San Francisco.
  34. Nicoletta Batini & Joe Pearlman, 2002. "Too Much Too Soon: Instability and Indeterminacy with Forward-Looking Rules," Computing in Economics and Finance 2002 182, Society for Computational Economics.
  35. Tetlow, Robert J. & von zur Muehlen, Peter, 2001. "Simplicity versus optimality: The choice of monetary policy rules when agents must learn," Journal of Economic Dynamics and Control, Elsevier, vol. 25(1-2), pages 245-279, January.
  36. Alexei Onatski & Noah Williams, 2003. "Modeling Model Uncertainty," NBER Working Papers 9566, National Bureau of Economic Research, Inc.
  37. Söderström, Ulf, 1999. "Monetary policy with uncertain parameters," Working Paper Series 83, Sveriges Riksbank (Central Bank of Sweden).
  38. Giannoni, Marc P., 2002. "Does Model Uncertainty Justify Caution? Robust Optimal Monetary Policy In A Forward-Looking Model," Macroeconomic Dynamics, Cambridge University Press, vol. 6(01), pages 111-144, February.
  39. Woodford, Michael, 1999. "Optimal monetary policy inertia," CFS Working Paper Series 1999/09, Center for Financial Studies (CFS).
  40. Ehrmann, Michael & Smets, Frank, 2001. "Uncertain potential output: implications for monetary policy," Working Paper Series 0059, European Central Bank.
  41. Clarida, Richard & Galí, Jordi & Gertler, Mark, 1999. "The Science of Monetary Policy: A New Keynesian Perspective," CEPR Discussion Papers 2139, C.E.P.R. Discussion Papers.
  42. Marvin Goodfriend & Robert G. King, 1998. "The new neoclassical synthesis and the role of monetary policy," Working Paper 98-05, Federal Reserve Bank of Richmond.
  43. Richard Clarida & Jordi Gali & Mark Gertler, 1997. "Monetary Policy Rules in Practice: Some International Evidence," NBER Working Papers 6254, National Bureau of Economic Research, Inc.
  44. Bray, Margaret M & Savin, Nathan E, 1986. "Rational Expectations Equilibria, Learning, and Model Specification," Econometrica, Econometric Society, vol. 54(5), pages 1129-60, September.
  45. Hansen, Lars Peter & Sargent, Thomas J., 2003. "Robust control of forward-looking models," Journal of Monetary Economics, Elsevier, vol. 50(3), pages 581-604, April.
  46. Giannitsarou, Chryssi, 2005. "E-Stability Does Not Imply Learnability," Macroeconomic Dynamics, Cambridge University Press, vol. 9(02), pages 276-287, April.
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Cited by:
  1. Ludwig, Alexander & Zimper, Alexander, 2014. "Biased Bayesian learning with an application to the risk-free rate puzzle," Journal of Economic Dynamics and Control, Elsevier, vol. 39(C), pages 79-97.
  2. Mostafavi, Moeen & Fatehi, Ali-Reza & Shakouri G., Hamed & Von zur Muehlen, Peter, 2011. "A predictive multi-agent approach to model systems with linear rational expectations," MPRA Paper 35351, University Library of Munich, Germany, revised 11 Dec 2011.
  3. Martin Ellison & Thomas J. Sargent, 2012. "A Defense Of The Fomc," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 53(4), pages 1047-1065, November.
  4. Evans , George W & Honkapohja, Seppo, 2007. "Expectations, learning and monetary policy: an overview of recent research," Research Discussion Papers 32/2007, Bank of Finland.
  5. Heinz-Peter Spahn, 2009. "The New Keynesian Microfoundations of Macroeconomics," Diskussionspapiere aus dem Institut für Volkswirtschaftslehre der Universität Hohenheim 317/2009, Department of Economics, University of Hohenheim, Germany.
  6. Mostafavi, Moeen & Shakouri G., Hamed & Fatehi, Ali-Reza, 2010. "Why the determinacy condition is a weak criterion in rational expectations models," MPRA Paper 28320, University Library of Munich, Germany.

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