optimal monetary policy in an economy with inflation persistence abstract this paper studies optimal monetary policy in a model where inflation is persistent two types of price setters are assumed to exist one acts rationally given calvo type constraints on price setting the other type sets prices according to a rule of thumb this results in a phillips curve with both a forward looking term and a backward looking term the phillips curve nests a standard purely forward looking phillips curve as well as a standard purely backward looking phillips curve as special cases a cost push supply shock is derived from microfoundations by adding a time varying income tax and by making the elasticity of substitution between goods stochastic a central bank loss function for this model is derived from a second order taylor approximation of the household s welfare function optimal monetary policy for different relative values of the forward and backward looking terms is then analyzed for both the commitment case and the case of discretion

monetary policy learning and the speed of convergence under the assumption of bounded rationality economic agents learn from their past mistaken predictions by combining new and old information to form new beliefs the purpose of this paper is to investigate how the policy maker by affecting private agents learning process determines the speed at which the economy converges to the rational expectation equilibrium i find that by reacting strongly to private agents expected inflation a central bank increases the speed of convergence and shortens the length of the transition to the rational expectation equilibrium i use speed of convergence as an additional criterion for evaluating alternative monetary policies i find that a fast convergence is not always desirable

performance of monetary policy with internal central bank forecasting abstract recent models of monetary policy have analyzed the desirability of different optimal and ad hoc interest rules under the restrictive assumption that forecasts of the private sector and the central bank are homogeneous this paper studies the implications of heterogeneity in forecasting by the central bank and private agents for the performance of interest rules in a framework of econometric learning

nominal price rigidity money supply endogeneity and business cycles abstract this paper investigates the ability of nominal price rigidity to explain the co movement of inflation with the cyclical component of output observed in the post war u s data a dynamic general equilibrium model is constructed with the introduction of monopolistic competition and nominal price rigidity in a standard real business cycle model allowing for an endogenous money supply rule it is then demonstrated that sticky price models can explain the observed associations between movements in inflation and output much better than flexible price models this result depends little on whether money supply is assumed to be endogenous or not

discretionary monetary policy and the zero lower bound on nominal interest rates abstract ignoring the existence of the zero lower bound on nominal interest rates one considerably understates the value of monetary commitment in new keynesian models a stochastic forward looking model with an occasionally binding lower bound calibrated to the u s economy suggests that low values for the natural rate of interest lead to sizeable output losses and deflation under discretionary monetary policy the fall in output and deflation are much larger than in the case with policy commitment and do not show up at all if the model abstracts from the existence of the lower bound the welfare losses of discretionary policy increase even further when inflation is partly determined by lagged inflation in the phillips curve these results emerge because private sector expectations and the discretionary policy response to these expectations reinforce each other and cause the lower bound to be reached much earlier than under commitment

expectations and the stability problem for optimal monetary policies eine auf den fundamentaldaten beruhende regelbindung der geldpolitik ohne selbstverpflichtung die bei vollkommen rationalen erwartungen der privaten akteure optimal ware ist instabil wenn diese akteure de facto den ublichen regeln des adaptiven lernens folgen dieses problem lasst sich dadurch beheben dass die erwartungen privater akteure berucksichtigt und in geeigneter weise in die optimale geldpolitik einbezogen werden diese eindeutige schlusfolgerung gilt auch dann wenn sich der geldpolitische entscheidungstrager und die privaten akteure in einem simultanen lernprozess befinden unsere ergebnisse zeigen wie wichtig es ist die geldpolitik angemessen zu gestalten und dabei nicht nur die fundamentaldaten sondern auch direkt die beobachteten erwartungen privater haushalte und unternehmen zu berucksichtigen

behavioural heterogeneity under evolutionary pressure macroeconomic implications of costly optimisation a model is developed in which a continuum of agents makes interdependent output decisions in a stochastic environment characterised by strategic complementarity two groups are distinguished naive agents follow a costless adaptive expectations rule while sophisticated agents incur an optimisation cost to achieve self fulfilling expectations the paper studies the dynamics generated as the population composition evolves under pressure of differential payoffs sophisticated agents are favoured if optimisation is cheap or the stochastic environment highly variable but naive agents generally persist a higher long run share of sophisticated agents is associated with greater output variability and low output persistence several attempts have been made in the recent macroeconomic literature to explore the implications of allowing for behavioural heterogeneity among economic agents typically the standard postulates of unbounded rationality are held to apply only to a subset of the population while the remainder is assumed to behave in accordance with some alternative specification the nature of which depends on the situation being analysed akerlof and yellen

some implications of learning for price stability abstract survey data on expectations of a range of macroeconomic variables exhibit low frequency drift in a new keynesian model consistent with these empirical properties optimal policy in general delivers a positive inflation rate in the long run two special cases deliver classic outcomes under rational expectations as the degree of low frequency variation in beliefs goes to zero the long run inflation rate coincides with the inflation bias under optimal discretion for non zero low frequency drift in beliefs as households become highly patient valuing utility in any period equally the optimal long run inflation rate coincides with optimal commitment price stability is optimal the optimal state contingent response to cost push disturbances similarly reflects properties of optimal discretion and optimal commitment depending on the degree of low frequency variation in beliefs when beliefs exhibit substantial variation in response to short run forecast errors optimal policy is closer to commitment

is inflation sticky abstract new keynesian sticky price models predict that monetary policy can affect real variables however they also predict that inflation can be reduced without depressing output or employment in fact bringing down inflation is costly presenting a challenge to the new keynesian model two departures from the new keynesian model predict costly disinflation one assumes sticky inflation rather than sticky prices while the other assumes less than perfectly rational expectations taking into account information from surveys of inflation expectations i find the evidence suggests that inflation is not sticky and that inflation expectations are less than perfectly rational

intrinsic heterogeneity in expectation formation we introduce the concept of misspecification equilibrium to dynamic macroeconomics agents choose between a list of misspecified econometric models and base their selection on relative forecast performance a misspecification equilibrium is a stochastic process in which agents forecast optimally given their choices with forecast model parameters and predictor proportions endogenously determined under appropriate conditions the misspecification equilibrium will exhibit intrinsic heterogeneity in which all predictors are used at all times even in the neoclassical limit in which only the most successful predictors are used this equilibrium is attainable under least squares learning and dynamic predictor selection based on average profits

investigating inflation persistence across monetary regimes under inflation targeting estimates of the indexation parameter in hybrid new keynesian phillips curves are either equal to zero or very low in the united kingdom canada sweden and new zealand analogous results hold for the euro area under the european monetary union and for switzerland under the new monetary regime under stable regimes with clearly defined nominal anchors inflation appears to be purely forward looking these results question the notion that the intrinsic inflation persistence found in post wwii u s data is structural in the sense of lucas carnegie rochester conference series on public policy 1 1976 19 46 and suggest that hardwiring inflation persistence in macroeconomic models is potentially misleading

learning about monetary policy rules abstract we study macroeconomic systems with forward looking private sector agents and a monetary authority that is trying to control the economy through the use of a linear policy feedback rule we use stability under recursive learning a la evans and honkapohja learning and expectations in macroeconomics princeton university press princeton new jersey 2001 as a criterion for evaluating monetary policy rules in this context we find that considering learning can alter the evaluation of alternative policy rules

volatility transmission in emerging european foreign exchange markets abstract this paper studies the dynamics of volatility transmission between central european ce currencies and the eur usd foreign exchange using model free estimates of daily exchange rate volatility based on intraday data we formulate a flexible yet parsimonious parametric model in which the daily realized volatility of a given exchange rate depends both on its own lags as well as on the lagged realized volatilities of the other exchange rates we find evidence of statistically significant intra regional volatility spillovers among the ce foreign exchange markets with the exception of the czech and prior to the recent turbulent economic events polish currencies we find no significant spillovers running from the eur usd to the ce foreign exchange markets to measure the overall magnitude and evolution of volatility transmission over time we construct a dynamic version of the diebold yilmaz volatility spillover index and show that volatility spillovers tend to increase in periods characterized by market uncertainty

interpreting inflation persistence comments on the conference on quantitative evidence on price determination the past decade has seen important advances in the analysis of price setting behavior most notably in my view a great deal of effort has been directed at the development of models that on the one hand have an explicit behavioral interpretation the models are clear about who sets prices what they seek to achieve when choosing prices and to what constraints they are subject when making the decision and at the same time can be parameterized so as to be compared in detail to inflation data this has allowed these models to be incorporated into complete dsge models of business fluctuations and of the monetary transmission mechanism that can be econometrically estimated this raises the prospect that it should soon be possible to base policy analysis on models that are both quantitatively realistic and plausibly invariant under the kinds of changes in policy that the analyst may wish to contemplate some argue that these two desiderata remain in considerable tension with one another that one cannot insist upon optimizing foundations at least under the current state of knowledge without substantial sacrifice of quantitative realism it is somewhat unfair however to present the quest for a model with optimizing foundations as a retreat from full insistence upon empirical realism given the fact that models with clear behavioral interpretations can be checked against a wider range of types of empirical evidence which should ultimately allow greater confidence in the realism of the specification that can withstand such scrutiny for example the exhaustive recent study of evidence on price setting in the euro area undertaken by the eurosystem s inflation persistence network compares alternative models in the light of three distinct

optimal fiscal and monetary policy in an economy without capital abstract this paper is concerned with the structure and time consistency of optimal fiscal and monetary policy in an economy without capital in a dynamic context optimal taxation means distributing tax distortions over time in a welfare maximizing way for a barter economy our main finding is that with debt commitments of sufficiently rich maturity structure an optimal policy if one exists is time consistent in a monetary economy the idea of optimal taxation must be broadened to include an inflation tax and we find that time consistency does not carry over an optimal inflation tax requires commitment by rules in a sense that has no counterpart in the dynamic theory of ordinary excise taxes the reason time consistency fails in a monetary economy is that nominal assets should from a welfare maximizing point of view always be taxed away via an immediate inflation in a kind of capital levy this emerges as a new possibility when money is introduced into an economy without capital

the time consistency of optimal monetary and fiscal policies we show that optimal monetary and fiscal policies are time consistent for a class of economies often used in applied work economies appealing because they are consistent with the growth facts we establish our results in two steps we first show that for this class of economies the friedman rule of setting nominal interest rates to zero is optimal under commitment we then show that optimal policies are time consistent if the friedman rule is optimal for our benchmark economy in which the time consistency problem is most severe the converse also holds if optimal policies are time consistent then the friedman rule is optimal

optimal monetary policy when agents are learning abstract we derive optimal monetary policy in a sticky price model when private agents follow adaptive learning we show that this slight departure from rationality has important implications for policy design the central bank faces a new intertemporal trade off not present under rational expectations it is optimal to forego stabilizing the economy in the present in order to facilitate private sector learning and thus ease the future intratemporal inflation output gap trade offs the policy recommendation is robust the welfare loss entailed by optimal policy under learning if the private sector actually has rational expectations is much smaller than if the central bank mistakenly assumes rational expectations when in fact agents are learning

learning with expert advice surveys of inflation forecasts show that expectations combine forward looking and backwardlooking elements this contradicts conventional wisdom in the presence of rational agents adaptiveagentswouldbedrivenoutofthemarket inourpaper werationalizethisfindinginan equilibrium framework our model has two types of agents one having rational expectations and the other using adaptive learning the proportion of these agents in the population evolves according to their past forecasting performance we show that even an underparameterized learning algorithm survives competition with rational expectations jel c62 d83 d84

adaptive learning persistence and optimal monetary policy we show that when private sector expectations are determined in line with adaptive learning optimal policy responds persistently to cost push shocks the optimal response is stronger and more persistent the higher is the initial level of perceived inflation persistence by the private sector such a sophisticated policy reduces inflation persistence and inflation volatility at little cost in terms of output gap volatility persistent responses to cost push shocks and stability of inflation expectations resemble optimal policy under commitment and rational expectations nevertheless it is clear that the mechanism at play is very different in the case of commitment it relies on expectations of future policy actions affecting inflation expectations in the case of sophisticated central banking it relies on the reduction in the estimated inflation persistence parameter based on inflation data generated by shocks and policy responses jel e52

imperfect credibility and inflation persistence in this paper we formulate a dynamic general equilibrium model with staggered nominal contracts in which households and rms use optimal ltering to disentangle persistent and transitory shifts in the monetary policy rule the calibrated model accounts quite well for the dynamics of output and insation during the volcker disinsation and implies a sacri ce ratio very close to the estimated value our approach indicates that insation persistence and substantial costs of disinsation can be generated in an optimizing agent framework without relaxing the assumption of rational expectations or relying on arbitrary modi cations to the aggregate supply relation jel classi cation e31 e32 e52

learning in an estimated medium scale dsge model in this paper we evaluate the empirical relevance of learning by private agents in an estimated medium scale dsge model we replace the standard rational expectation assumption in the smets and wouters 2007 model by a constant gain learning mechanism if agents know the correct structure of the model and only learn about the parameters both expectation mechanisms resultin asimilarfit and onlythetransition dynamicsthatare generated byspecific initial beliefs can distinguish the two approaches if in addition agents use only a reduced information set in forming the perceived law of motion the implied model dynamics change and for some initial beliefs the marginal likelihood of the model is further improved however the estimated gain parameter is estimated to be small which suggests a crucial role for the initial beliefs to explain the improved fit the learning models with the highest posterior probabilities add some additional persistence to the dsge model that reduce the gap between the irfs of the dsge model and the more data driven dsge var model however the additional dynamics that are introduced by the learning process do not systematically alter the estimated structural parameters related to the nominal and real frictions in the dsge model jel codes c11 d84 e30 e52

robustly optimal monetary policy with near rational expectations the paper considers optimal monetary stabilization policy in a forward look ing model when the central bank recognizes that private sector expectations need not be precisely model consistent and wishes to choose a policy that will be as good as possible in the case of any beliefs that are close enough to model consistency it is found that commitment continues to be important for optimal policy that the optimal long run inflation target is unaffected by the degree of potential distortion of beliefs and that optimal policy is even more history dependent than if rational expectations are assumed jel c62 d84 el 3 e31 e32 e52 an extensive literature has considered the optimal conduct of monetary policy under the assumption of rational or model consistent expectations this literature has found that it is quite important to take account of the effects of the systematic and hence predictable compo nent of monetary policy on expectations for example it is found quite generally that an optimal policy commitment differs from the policy that would be chosen through a sequential optimiza tion procedure with no advance commitment of future policy it is also found quite generally that optimal policy is history dependent a function of past conditions that no longer affect the degree to which it would be possible to achieve stabilization aims from the present time onward 1 both of these conclusions depend critically however on the idea that an advance commitment of future policy should change people s expectations at earlier dates this may lead to the fear that analyses that assume rational expectations re exaggerate the degree to which a policy authority can rely upon private sector expectations to be shaped by its policy commitments in precisely the way that it expects them to be what if the relation between what a central bank plans to do and what the public will expect to happen is not quite so predictable might both the case for advance commitment of policy and the case for history dependent policy be considerably weakened under a more skeptical view of the precision with which the public s expectations can be predicted one way of relaxing the assumption of rational expectations is to model agents as forecasting using an econometric model the coefficients of which they must estimate using data observed prior to some date sampling error will then result in forecasts that depart somewhat from pre cise consistency with the analyst s model 2 however selecting a monetary policy rule on the basis of its performance under a specific model of learning runs the risk of exaggerating the degree to which the policy analyst can predict and hence exploit the forecasting errors that result from a particular way of extrapolating from past observations one might even conclude

optimal fiscal policy under learning abstract this paper characterizes optimal fiscal policy when agents learn about future taxation a benevolent and fully rational government chooses taxes on labor income and state contingent bonds to finance public spending considering that private agents form their expectations through a learning algorithm facing a trade off between distortionary taxes and distorted expectations the ramsey planner chooses the policy that minimizes the total cost of distortions the analysis produces two main results first the government will use fiscal variables to manipulate expectations reducing taxes and issuing debt at times of pessimism and doing the opposite at times of optimism this speeds up learning second the expectation dependent fiscal plan is also history dependent and it prescribes taxes that are not as smooth and more persistent than under rational expectations these findings are robust to alternative learning algorithms

durable goods leasing in the presence of exporting used products to an international secondary market abstract with the rapid growth of global trade used durable goods from wealthy countries increasingly find their way into the secondary market of less wealthy countries exporting used products to a physically separate market not only removes cannibalization for new products at home but also fetches additional revenue in this paper we investigate the implications of exporting used products to international secondary markets in the durable goods industry we find that such a practice may significantly stimulate new product lease on the home market an effect in which the market attractiveness and product quality are mutually reinforcing we discover that removing cannibalization pressure is more of a priority than generating additional revenue while exporting used products if the export is carried out by an agent who exports used products bought from oem original equipment manufacturer we observe the disadvantage of double marginalization in a channel structure which slows down export and causes quantity distortion and also reduces the effectiveness of government stimulus however if the agent and oem set export price based supply and demand equilibrium this reduces the quantity distortion one special characteristic of used products trade across borders is the involvement of governments on both sides of the border the government measures include penalties imposed on aging durable goods and trade barriers we find that legislation of penalizing used products on the domestic market can stimulate export but it does not have an intended effect of stimulating new products produced at home the channel structure worsens the problem

recurrent hyperinflations and learning we use a model of boundedly rational learning to account for the observations of recurrent hyperinflations in the 1980 s in a standard monetary model we replace the assumption of full rational expectations by a formal definition of quasi rational learning the model under learning matches some crucial stylized facts observed during the recurrent hyperinflations experienced by several countries in the 1980 s remarkably well we argue that despite being a small departure from rational expectations quasi rational learning does not preclude falsifiability of the model it does not violate reasonable rationality requirements and it can be used for policy evaluation

a simple recursive forecasting model abstract we compare the performance of alternative recursive forecasting models a simple constant gain algorithm used widely in the learning literature both forecasts well out of sample and also provides the best fit to the survey of professional forecasters

inflation dynamics and subjective expectations in the united states i introduction this paper analyzes the ability of sticky price models to explain the dynamics of u s inflation when using survey data as proxies for inflation expectations testing sticky price models with survey expectations is attractive since to the extent that survey data correctly capture agents expectations they allow to disregard issues related to the specification of agents expectations functions one neither has to impose untested orthogonality restrictions as required when estimating under the assumption of rational expectations nor has to make restrictive assumptions about the precise form of nonrationality present in agents forecast functions this allows to focus on the question whether the economic models under consideration are correctly specified previous tests of sticky price models performed under the assumption that agents hold rational expectations have generated mixed results prominently fuhrer and moore 1995 have reported that sticky price models do not generate sufficient stickiness for inflation when the output gap is used as a measure of real marginal costs recent evidence however has shown that the empirical performance depends crucially on how one measures real marginal costs the main determinant of inflation according to sticky price models for instance gall and gertler 1999 and sbordone 2002 show that sticky price models perform well once marginal costs are approximated by average unit labor costs 1 it makes an important difference whether sticky price models successfully explain inflation dynamics as a function of output behavior or they relate inflation dynamics to the behavior of unit labor costs given that the ultimate objective is a model explaining the joint behavior of output and inflation the latter case would require an additional empirically plausible theory linking the dynamics of unit labor costs to the behavior of output this paper studies whether the currently popular new keynesian phillips curve nkpc which can be derived from calvo 1983 style sticky price models is able to explain a relationship between inflation on the one hand and output or unit labor costs on the other hand thus we let the data speak whether a theory linking output to costs is warranted once expectations are approximated by data reported in the survey of professional forecasters our main finding is that the nkpc performs equally well with both measures of marginal costs output and unit labor costs whatever measure is used the estimate of the quarterly discount factor is close to one and the point estimate of the degree of price stickiness implies that firms reset their prices roughly every five quarters on average these results suggest that potential nonrationalities in expectations as they show up in surveys have biased previous estimates using output as a measure for marginal costs quite surprisingly the same nonrationalities do not seem to play a role when using unit labor costs here our estimates confirm the results obtained by gall and gertler 1999 and sbordone 2002 who assumed rational expectations we show that the reason for this finding is that approximating the agents information set using the unit labor cost variable rests on more solid grounds than approximating it using the output variable in particular the survey data suggest that the hypothesis of rational expectations implies a too high correlation between lagged output and future inflation expectations we show that this causes the coefficient estimate for output to become negative contrary to what is implied by theory these results suggest that once one takes account of potentially nonrational expectations via survey expectations sticky price models are able to establish a close link between output dynamics and the behavior of inflation to assess the robustness of this finding we include into the price equation lags of various variables and test for their significance

optimal commitment policy under noisy information abstract this paper studies an advantage of commitment over discretion when a central bank observes only noisy measures of current inflation and output in the context of an optimizing model with nominal price stickiness under a commitment regime if current policy turns out to be too expansionary contractionary because of the bank s information problem subsequent policies should be slightly contractionary expansionary by following this approach the central bank can improve the trade off between the fluctuations of its goal variables caused by economic shocks and their fluctuations caused by the bank s response to measurement error

the tragedy of uk fiscal policy in the aftermath of the financial crisis the evolving response of the uk fiscal authorities to the financial crisis and recession are briefly outlined with a focus on the fiscal austerity programme introduced by the incoming coalition government during 2010 the reasoning for that programme is critically examined and largely dismissed it is argued that the drive for major cuts in public expenditure comes from seeking to achieve a balanced structural budget and reductions in estimated potential output the significance of the latter are discussed the paper is completed by a brief consideration of alternatives

learning by doing and the value of optimal experimentation abstract recent research on learning by doing has provided the limit properties of beliefs and actions for a class of learning problems in which experimentation is an important aspect of optimal decision making however under these conditions the optimal policy cannot be derived analytically because bayesian learning about unknown parameters introduces a nonlinearity in the dynamic optimization problem this paper utilizes numerical methods to characterize the optimal policy function for a learning by doing problem that is general enough for practical economic applications the optimal policy is found to incorporate a substantial degree of experimentation under a wide range of initial beliefs about the unknown parameters dynamic simulations indicate that optimal experimentation dramatically improves the speed of learning and the stream of future payoffs furthermore these simulations reveal that a policy which separates control and estimation and does not incorporate experimentation frequently induces a long lasting bias in the control and target variables while these sequences tend to converge steadily under the optimal policy they frequently exhibit non stationary behavior when estimation and control are treated separately

expectational stability and the multiple equilibria problem in linear rational expectations models linear models involving expectations of future endogenous variables generally have multiple rational expectations equilibria this paper investigates the stability of solutions in the disequilibrium sense of whether given a small deviation of expectations functions from some rational expectations equilibrium the system returns to that solution under a natural revision rule weak and strong local stability are distinguished stability conditions are calculated for a simple general linear model and applied to two macroeconomic examples in some cases there is a unique stable equilibrium in other cases a continuum of equilibria forms a weakly but not strongly stable class

aggressive oil extraction and precautionary saving coping with volatility the effects of stochastic oil demand on optimal oil extraction paths and tax spending and government debt policies are analyzed when the oil demand schedule is linear and preferences quadratic without prudence optimal oil extraction is governed by the hotelling rule and optimal budgetary policies by the tax and consumption smoothing principle volatile oil demand brings forward oil extraction and induces a bigger government surplus with prudence the government depletes oil reserves even more aggressively and engages in additional precautionary saving financed by postponing spending and bringing taxes forward especially if it has substantial monopoly power on the oil market gives high priority to the public spending target is very prudent and future oil demand has high variance uncertain economic prospects induce even higher precautionary saving and if non oil revenue shocks and oil revenue shocks are positively correlated even more aggressive oil extraction in contrast prudent governments deliberately underestimate oil reserves which induce less aggressive oil depletion and less government saving but less so if uncertainty about reserves and oil demand are positively correlated

monetary policy expectations and commitment commitment in monetary policy leads to equilibria that are superior to those from optimal discretionary policies a number of interest rate reaction functions and instrument rules have been proposed to implement or approximate commitment policy we assess these rules in terms of whether they lead to a rational expectations equilibrium that is both locally determinate and stable under adaptive learning by private agents a reaction function that appropriately depends explicitly on private sector expectations performs particularly well on both counts

the performance of forecast based monetary policy rules under model uncertainty we investigate the performance of forecast based monetary policy rules using five macroeconomic models that reflect a wide range of views on aggregate dynamics we identify the key characteristics of rules that are robust to model uncertainty such rules respond to the one year ahead inflation forecast and to the current output gap and incorporate a substantial degree of policy inertia in contrast rules with longer forecast horizons are less robust and are prone to generating indeterminacy in light of these results we identify a robust benchmark rule that performs very well in all five models over a wide range of policy preferences