Deviations from rules-based policy and their effects

Rules-based monetary policy evaluation has long been central to macroeconomics. Using the original Taylor rule, a modified Taylor rule with a higher output gap coefficient, and an estimated Taylor rule, we define rules-based and discretionary eras by smaller and larger policy rule deviations, the absolute value of the difference between the actual federal funds rate and the federal funds rate prescribed by the three rules. We use tests for multiple structural changes to identify the eras so that knowledge of subsequent economic outcomes cannot influence the choice of the dates. With the original Taylor rule, monetary policy in the U.S. is characterized by a rules-based era until 1974, a discretionary era from 1974 to 1985, a rules-based era from 1985 to 2000, and a discretionary era from 2001 to 2013. With the modified Taylor rule, the rules-based era extends further into the 1970s and there is an additional rules-based period starting in 2006. We calculate various loss functions and find that economic performance is uniformly better during rules-based eras than during discretionary eras, and that the original Taylor rule provides the largest loss during discretionary periods relative to loss during rules-based periods.     

Should the monetary policy rule be different in a financial crisis?

This article reviews the finding that standard loss functions in output and inflation are higher during discretionary periods than in periods during which monetary policy is described by a rule, such as the Taylor rule. It shows that the finding is consistent with earlier research, but argues that we really do not know if the Taylor rule would have improved performance during the recent financial crisis. The article then considers modifications of policy rules to deal with changes in interest rate spreads, credit aggregates and banks׳ balance sheets.     

Model uncertainty and policy evaluation: Some theory and empirics

This paper explores ways to integrate model uncertainty into policy evaluation. We describe a general framework that includes both model averaging methods as well as some measures that describe whether policies and their consequences are model dependent. These general ideas are then applied to assess simple monetary policy rules for some standard New Keynesian specifications. We conclude that the original Taylor rule has good robustness properties, but may reasonably be challenged in overall quality with respect to stabilization by alternative simple rules, even when these rules employ parameters that are set without accounting for model uncertainty.     

Robust optimal monetary policy in a forward‐looking model with parameter and shock uncertainty

This paper characterizes a robust optimal policy rule in a simple forward‐looking model, when the policymaker faces uncertainty about model parameters and shock processes. We show that the robust optimal policy rule is likely to involve a stronger response of the interest rate to fluctuations in inflation and the output gap than is the case in the absence of uncertainty. Thus parameter uncertainty alone does not necessarily justify a small response of monetary policy to perturbations. However, uncertainty may amplify the degree of ‘super‐inertia’ required by optimal monetary policy. We finally discuss the sensitivity of the results to alternative assumptions. Copyright © 2007 John Wiley & Sons, Ltd.     

Optimal monetary policy in a new Keynesian model with animal spirits and financial markets

This article presents a macro-finance-interaction model that integrates a NKM with bounded rationality and an agent-based financial market model. We derive four interactive channels between the two sectors where two channels are strictly microfounded. We analyze the impact of the different channels on economic stability and derive optimal (conventional and unconventional) monetary policy rules. We find that coefficients of optimal Taylor rules do not significantly change if financial market stabilization becomes part of the central bank׳s objective function. Additionally, we show that rule-based, backward-looking monetary policy creates huge instabilities if expectations are boundedly rational. Our model is externally validated by showing that it generates fat tailed output growth rates.     

The zero lower bound,the dual mandate,and unconventional dynamics

This paper examines monetary policy when it is constrained by the zero lower bound (ZLB) on the nominal interest rate. Our analysis uses a nonlinear New Keynesian model with technology and discount factor shocks. Specifically, we investigate why technology shocks may have unconventional effects at the ZLB, what factors affect the likelihood of hitting the ZLB, and the implications of alternative monetary policy rules. We initially focus on a New Keynesian model without capital (Model 1) and then study that model with capital (Model 2). The advantage of including capital is that it introduces another mechanism for intertemporal substitution that strengthens the expectational effects of the ZLB. Four main findings emerge: (1) In Model 1, the choice of output target in the Taylor rule may reverse the effects of technology shocks when the ZLB binds; (2) When the central bank targets steady-state output in Model 2, a positive technology shock at the ZLB leads to more pronounced unconventional dynamics than in Model 1; (3) The presence of capital changes the qualitative effects of demand shocks and alters the impact of a monetary policy rule that emphasizes output stability; and (4) In Model 1, the constrained linear solution is a decent approximation of the nonlinear solution, but meaningful differences exist between the solutions in Model 2.     

Learning about monetary policy rules when the cost-channel matters

We study how monetary policy may affect determinacy and expectational stability (E-stability) of rational expectations equilibrium when the cost channel of monetary policy matters. Focusing on instrumental Taylor-type rules and optimal target rules, we show that standard policies can induce indeterminacy and expectational instability when the cost channel is present. A naïve application of the traditional Taylor principle could be misleading, and expectations-based reaction function under discretion does not always induce determinate and E-stable equilibrium. This result contrasts with the findings of Bullard and Mitra [2002. Learning about monetary policy rules. Journal of Monetary Economics 49, 1105–1129] and Evans and Honkapohja [2003. Expectations and stability problem for optimal monetary policies. Review of Economic Studies 70, 807–824] for the standard new Keynesian model. The ability of the central bank to commit to an optimal policy is an antidote to these problems.     

On the desirability of nominal GDP targeting

This paper evaluates the welfare properties of nominal GDP targeting in the context of a New Keynesian model with both price and wage rigidity. In particular, we compare nominal GDP targeting to inflation and output gap targeting as well as to a conventional Taylor rule. These comparisons are made on the basis of welfare losses relative to a hypothetical equilibrium with flexible prices and wages. Output gap targeting is the most desirable of the rules under consideration, but nominal GDP targeting performs almost as well. Nominal GDP targeting is associated with smaller welfare losses than a Taylor rule and significantly outperforms inflation targeting. Relative to inflation targeting and a Taylor rule, nominal GDP targeting performs best conditional on supply shocks and when wages are sticky relative to prices. Nominal GDP targeting may outperform output gap targeting if the gap is observed with noise, and has more desirable properties related to equilibrium determinacy than does gap targeting.     

Hungary's entry into the euro area: Lessons for prospective members from a monetary policy perspective

This paper evaluates the conduct of monetary policy in Hungary using standard Taylor rules as well as extended rules that incorporate real exchange rate effects. Moreover, we explicitly consider the impact of future euro area entry by estimating instrument rules that permit an influence from Maastricht Treaty inflation requirements via the estimation of Markov switching models as well as by estimating a differential rule vis-à-vis the existing euro area. Lastly, the paper also considers the impact on policy rules from the large data revision that affects real exchange rate and output estimates. I find that interest rate setting behavior in Hungary does not resemble that of the euro area. Also, counterfactual experiments reveal that the potential macroeconomic costs of entry into the euro area sooner rather than later may be lower than if membership in the single currency area is delayed beyond 2008.     

Optimal monetary policy in a regime-switching economy: The response to abrupt shifts in exchange rate dynamics

This paper examines the trade-offs that a central bank faces when the exchange rate can experience sustained deviations from fundamentals and occasionally collapse. The economy is modelled as switching randomly between different regimes according to time-invariant transition probabilities. We compute both the optimal regime-switching control rule for this economy and optimised linear Taylor rules, in the two cases where the transition probabilities are known with certainty and where they are uncertain. The simple algorithms used in the computation are also of independent interest as tools for the study of monetary policy under general forms of (asymmetric) additive and multiplicative uncertainty. An interesting finding is that policies based on robust (minmax) values of the transition probabilities are usually more conservative.     

Macroeconomic and financial stability in a monetary union: The case of Lithuania

In this paper, we study the implications of macroprudential policies in a monetary union for macroeconomic and financial stability. For this purpose, we develop a two-country monetary union new Keynesian general equilibrium model with housing and collateral constraints, to be calibrated for Lithuania and the rest of the euro area. We consider two different scenarios for macroprudential policies: one in which the ECB extends its goals to also include financial stability and a second one in which a national macroprudential authority uses the loan-to-value ratio (LTV) as an instrument. The results show that both rules are effective in making the financial system more stable in both countries, and especially in Lithuania. This is because the financial sector in this country is more sensitive to shocks. We find that an extended Taylor rule is indeed effective in reducing the volatility of credit, but comes with a cost in terms of higher inflation volatility. The simple LTV rule, on the other hand, does not compromise the objective of monetary policy. This reinforces the “Tinbergen principle”, which argues that there should be two different instruments when there are two different policy goals.     

Monetary policy in open economies: Practical perspectives for pragmatic central bankers

This paper reviews and interprets some of the key policy implications that flow from a class of DSGE models for optimal monetary policy in the open economy. The framework suggests that good macroeconomic outcomes in open economies are possible by focusing inflation targeting that is implemented by a Taylor type rule, a rule that in equilibrium is reflected in the exchange rate as an asset price. Optimal monetary policy will not be able deliver a stationary (‘stable’) nominal exchange rate – let alone a fixed exchange rate or one that remains inside a target zone – because, absent a commitment device, optimal monetary can’t deliver a stationary domestic price level. Another feature in the data for inflation targeting countries that is consistent with monetary policy via Taylor type rule is that it will tend push the nominal exchange rate in the opposite direction from PPP in response to an ‘inflation’ shock—the ‘bad news god news’ result of Clarida and Waldman (2008. Is Bad News about Inflation Good News for the Exchange Rate. In: John Campbell, (Ed.), Asset Prices and Monetary Policy, Chicago: University of Chicago Press), Clarida and Waldman (2014. Bad News About Inflation is Good News for the Nominal Exchange Rate Under Optimal Monetary Policy: DSGE Theory and a Decade of Empirical Evidence). This is so even though in the long run of these models the nominal exchange rate must in expectation obey PPP.     

When should central bankers be fired?

In recent years, a number of countries have changed their central banking institutions. Often these reforms involve granting long terms of office to central bankers. This threatens to limit the extent to which the central bank can be held accountability. Dismissal rules can help ensure accountability, and, in the presence of inflation shocks, the socially optimal commitment policy is supported by a dismissal rule similar to a modified nominal income rule. The government's promise to follow the rule is shown to be credible in a trigger strategy equilibrium for reasonable parameter values. Received: March 26, 1999 / Accepted: September 20, 2001     

Monetary and fiscal policy under deep habits

Allowing habits to be formed at the level of individual goods – deep habits - can radically alter the fiscal policy transmission mechanism as the counter-cyclicality of mark-ups this implies can result in government spending crowding-in rather than crowding-out private consumption in the short run. We explore the robustness of this mechanism to the existence of price discrimination in the supply of goods to the public and private sectors. We then describe optimal monetary and fiscal policy in our New Keynesian economy subject to the additional externality of deep habits and explore the ability of simple policy rules to mimic fully optimal policy. We find that the presence of deep habits at empirically estimated levels can imply large externalities that significantly affect the conduct of monetary and tax policy. However, despite the rise in government spending multipliers implied by deep habits, government spending is barely used as a stabilisation tool under the optimal policy.     

Monetary policy transmission in a model with animal spirits and house price booms and busts

Can monetary policy trigger pronounced boom-bust cycles in house prices and create persistent business cycles? We address this question by building heuristics into an otherwise standard DSGE model. As a result, monetary policy sets off waves of optimism and pessimism (“animal spirits”) that drive house prices, that, in turn, have strong repercussions on the business cycle. We compare our findings to a standard model with rational expectations by means of impulse responses. We suggest that a standard Taylor rule is not well-suited to maintain macroeconomic stability. Instead, an augmented rule that incorporates house prices is shown to be superior.     

Optimal monetary policy using an unrestricted VAR

This paper proposes a simple benchmark for monetary policy. Assuming the true model of the economy is unknown, it is based on an unrestricted vector autoregression (VAR). The key result is that instead of deriving optimal policy using the original VAR equations as the constraint, when no restriction is placed on the correlation structure of the VAR disturbances, the constraint should be formed from a transformation of the VAR. This method is applied to the USA, 1964–2009. Significant welfare gains are found compared with actual policy and using a Taylor rule. Incorporating a zero interest rate lower bound lowers output and inflation. Copyright © 2010 John Wiley & Sons, Ltd.     

Optimal taxation in an RBC model: A linear-quadratic approach

We reconsider the optimal taxation of income from labor and capital in the stochastic growth model analyzed by Chari et al. [1994. Optimal fiscal policy in a business cycle model. Journal of Political Economy 102, 617–652; 1995. Policy analysis in business cycle models. In: Cooley, T.F. (Ed.), Frontiers of Business Cycle Research. Princeton University Press, Princeton], but using a linear-quadratic (LQ) approximation to derive a log-linear approximation to the optimal policy rules. The example illustrates how inaccurate ‘naive’ LQ approximation – in which the quadratic objective is obtained from a simple Taylor expansion of the utility function of the representative household – can be, but also shows how a correct LQ approximation can be obtained, which will provide a correct local approximation to the optimal policy rules in the case of small enough shocks. We also consider the numerical accuracy of the LQ approximation in the case of shocks of the size assumed in the calibration of Chari et al. We find that the correct LQ approximation yields results that are quite accurate, and similar in most respects to the results obtained by Chari et al. using a more computationally intensive numerical method.     

A Bayesian approach to optimal monetary policy with parameter and model uncertainty

This paper undertakes a Bayesian analysis of optimal monetary policy for the U.K. We estimate a suite of monetary-policy models that include both forward- and backward-looking representations as well as large- and small-scale models. We find an optimal simple Taylor-type rule that accounts for both model and parameter uncertainty. For the most part, backward-looking models are highly fault tolerant with respect to policies optimized for forward-looking representations, while forward-looking models have low fault tolerance with respect to policies optimized for backward-looking representations. In addition, backward-looking models often have lower posterior probabilities than forward-looking models. Bayesian policies therefore have characteristics suitable for inflation and output stabilization in forward-looking models.     

Estimating the Bank of Mexico’s reaction function in the last three decades: A Bayesian DSGE approach with rolling-windows

This paper uses a small open economy Dynamic Stochastic General Equilibrium (DSGE) model to investigate how Mexico’s central bank has conducted its monetary policy in the period 1995–2019. The main objective of the paper is to document the systematic changes in the Bank of Mexico’s reaction function by analyzing possible shifts in the parameters of the policy rule. The central bank’s policy is modeled using a Taylor rule that relates the nominal interest rate to output, inflation, and the exchange rate. I employ Bayesian computational techniques and conduct rolling-window estimations to explicitly show the transition of the policy coefficients over the sample period. Furthermore, the paper examines the macroeconomic implications of these changes through rolling-window impulse–response functions. The results suggest that the Bank of Mexico’s response to inflation has been steady since 1995, while the response to output and the exchange rate has decreased and stabilized after 2002.