Based on lectures given as part of The Stone Lectures in Economics, this book discusses the problem of formulating monetary policy in practice, under the uncertain circumstances which characterize the real world. The first lecture highlights the limitations of decision rules suggested by the academic literature and recommends an approach involving, first, a firm reliance on the few fundamental and robust results of monetary economics and, secondly, a pragmatic attitude to policy implementation, taking into consideration lessons from central banking experience. The second lecture revisits Milton Friedman's questions about the effects of active stabilization policies on business cycle fluctuations. It explores the implications of a simple model where the policy maker has imperfect knowledge about potential output and the private sector forms expectations according to adaptive learning. This lecture shows that imperfect knowledge limits the scope for active stabilization policy and strengthens the case for conservatism.

Based on lectures given as part of The Stone Lectures in Economics, this book discusses the problem of formulating monetary policy in practice, under the uncertain circumstances which characterize the real world. How should central banks set monetary policy? In which way should they take uncertainty into account when designing a monetary policy strategy? Should they respond to shocks aggressively or cautiously? These questions are discussed both with reference to the experience of the Bundesbank and of the European Central Bank and in relation to a simple stylized economic model.

Posing a major challenge to economic orthodoxy, Imperfect Knowledge Economics asserts that exact models of purposeful human behavior are beyond the reach of economic analysis. Roman Frydman and Michael Goldberg argue that the longstanding empirical failures of conventional economic models stem from their futile efforts to make exact predictions about the consequences of rational, self-interested behavior. Such predictions, based on mechanistic models of human behavior, disregard the importance of individual creativity and unforeseeable sociopolitical change. Scientific though these explanations may appear, they usually fail to predict how markets behave. And, the authors contend, recent behavioral models of the market are no less mechanistic than their conventional counterparts: they aim to generate exact predictions of "irrational" human behavior. Frydman and Goldberg offer a long-overdue response to the shortcomings of conventional economic models. Drawing attention to the inherent limits of economists' knowledge, they introduce a new approach to economic analysis: Imperfect Knowledge Economics (IKE). IKE rejects exact quantitative predictions of individual decisions and market outcomes in favor of mathematical models that generate only qualitative predictions of economic change. Using the foreign exchange market as a testing ground for IKE, this book sheds new light on exchange-rate and risk-premium movements, which have confounded conventional models for decades. Offering a fresh way to think about markets and representing a potential turning point in economics, Imperfect Knowledge Economics will be essential reading for economists, policymakers, and professional investors.

Over the past fifteen years, a significant number of industrialized and middle-income countries have adopted inflation targeting as a framework for monetary policymaking. As the name suggests, in such inflation-targeting regimes, the central bank is responsible for achieving a publicly announced target for the inflation rate. While the objective of controlling inflation enjoys wide support among both academic experts and policymakers, and while the countries that have followed this model have generally experienced good macroeconomic outcomes, many important questions about inflation targeting remain. In Inflation Targeting, a distinguished group of contributors explores the many underexamined dimensions of inflation targeting—its potential, its successes, and its limitations—from both a theoretical and an empirical standpoint, and for both developed and emerging economies. The volume opens with a discussion of the optimal formulation of inflation-targeting policy and continues with a debate about the desirability of such a model for the United States. The concluding chapters discuss the special problems of inflation targeting in emerging markets, including the Czech Republic, Poland, and Hungary.

We examine the performance and robustness properties of monetary policy rules in an estimated macroeconomic model in which the economy undergoes structural change andwhere private agents and the central bank possess imperfect knowledge about the true structure of the economy. Policymakers follow an interest rate rule aiming to maintain price stability and to minimize fluctuations of unemployment around its natural rate but areuncertain about the economy's natural rates of interest and unemployment and how private agents form expectations. In particular, we consider two models of expectations formation :rational expectations and learning. We show that in this environment the ability to stabilize the real side of the economy is significantly reduced relative to an economy under rational expectations with perfect knowledge. Furthermore, policies that would be optimal under perfect knowledge can perform very poorly if knowledge is imperfect. Efficient policies that take account of private learning and misperceptions of natural rates call for greater policy inertia, a more aggressive response to inflation, and a smaller response to the perceived unemployment gap than would be optimal if everyone had perfect knowledge of the economy. We show that such policies are quite robust to potential misspecification of private sector learning and the magnitude of variation in natural rates.