Monetary Policy And Asset Price Bubbles

A study of asset price bubbles and the implications for preventing financial instability.

An asset bubble relaxes collateral constraints and increases borrowing by credit-constrained agents. At the same time, as the bubble deflates when constraints start binding, it amplifies downturns. We show analytically and quantitatively that the macroprudential policy should optimally respond to building asset price bubbles non-monotonically depending on the underlying level of indebtedness. If the level of debt is moderate, policy should accommodate the bubble to reduce the incidence of a binding collateral constraint. If debt is elevated, policy should lean against the bubble more aggressively to mitigate the pecuniary externalities from a deflating bubble when constraints bind.

This volume critically re-examines the profession's understanding of asset bubbles in light of the global financial crisis of 2007-09. It is well known that bubbles have occurred in the past, with the October 1929 crash as the most demonstrative example. However, the remarkably well-behaved performance of the US economy from 1945 to 2006, and, in particular during the Great Moderation period of 1984 to 2006, assured the economics profession and monetary policymakers that asset bubbles could be effectively managed with little or no real economic impact. The recent financial crisis has now triggered a debate about the emergence of a sequence of repeated bubbles in the Nasdaq market, housing market, credit market, and commodity markets. The realities of the crisis have intensified theoretical modeling, empirical methodologies, and debate on policy issues surrounding asset price bubbles and their potentially adverse economic impact if poorly managed. Taking a novel approach, the editors of this book present five classic papers that represent accepted thinking about asset bubbles prior to the financial crisis. They also include original papers challenging orthodox thinking and presenting new insights. A summary essay highlights the lessons learned and experiences gained since the crisis.

Economic growth, low inflation, and financial stability are among the most important goals of policy makers, and central banks such as the Federal Reserve are key institutions for achieving these goals. In Asset Prices and Monetary Policy, leading scholars and practitioners probe the interaction of central banks, asset markets, and the general economy to forge a new understanding of the challenges facing policy makers as they manage an increasingly complex economic system. The contributors examine how central bankers determine their policy prescriptions with reference to the fluctuating housing market, the balance of debt and credit, changing beliefs of investors, the level of commodity prices, and other factors. At a time when the public has never been more involved in stocks, retirement funds, and real estate investment, this insightful book will be useful to all those concerned with the current state of the economy.

This book describes a laboratory experiment designed to test the causes and properties of bubbles in financial markets and explores the question whether it is possible to design markets which avoid such bubbles and crashes. In the experiment, subjects were given the opportunity to trade in a stock market modeled after the seminal work of Smith et al. (1988). To account for the increasing importance of online betting sites, subjects were also allowed to trade in a digital option market. The outcomes shed new light on how subjects form and update their expectations, placing special emphasis on the bounded rationality of investors. Various analytical bubble measures found in the literature are collected, calculated, classified and presented for the first time. The very interesting new bubble measures "Dispersion Ratio", "Overpriced Transactions" and "Underpriced Transactions" are developed, making the book an important step towards the research goal of preventing bubbles and crashes in financial markets.

The question of whether central banks should target stock prices so as to prevent bubbles and crashes from occurring has been hotly debated. This paper analyses this question using a behavioural macroeconomic model. This model generates bubbles and crashes. It analyses how 'leaning against the wind' strategies, which aim to reduce the volatility of stock prices, can help in reducing volatility of output and inflation. We find that such policies can be effective in reducing macroeconomic volatility, thereby improving the trade-off between output and inflation variability. The strength of this result, however, depends on the degree of credibility of the inflation-targeting regime. In the absence of such credibility, policies aiming at stabilising stock prices do not stabilise output and inflation.