Olivier J. Blanchard

THE SOLUTION OF LINEAR DIFFERENCE MODELS UNDER RATIONAL EXPECTATIONS

IN HIS SURVEY ON RATIONAL EXPECTATIONS, R. Shiller indicates that the difficulty of obtaining explicit solutions for linear difference models under rational expectations may have hindered their use [14, p. 27]. The present paper attempts to remedy that problem by giving the explicit solution for an important subclass of the model Shiller refers to as the general linear difference model. Section 1 presents the form of the model for which the solution is derived and shows how particular models can be put in this form. Section 2 gives the solution together with the conditions for existence and uniqueness. 1. THE MODEL The model is given by (la), (lb), and (1c) as follows:

Debt, Deficits, and Finite Horizons

Many issues in macroeconomics, such as the level of the steady state interest rate, or the dynamic effects of government deficit finance, depend crucially on the horizon of economic agents. This paper develops a simple analytical model in which such issues can be examined and in which the horizon of agents is a parameter which can be chosen arbitrarily.The first three sections of the paper characterize the dynamics and steady state of the economy in the absence of a government. The focus is on the effects of the horizon index on the economy. The paper clarifies in particular the separate roles of finite horizons and declining labor income through life in the determination of steady state interest rates.The next three sections study the effects and the role of fiscal policy.The focus is on the effects of deficit finance both in closed and open economies. The paper clarifies the respective roles of government spending, deficits and debt in the determination of interest rates.

Hysteresis and the European Unemployment Problem

European unemployment has been steadily increasing for the last fifteen years and is expected to remain very high for many years to come. In this paper, we argue that this fact implies that shocks have much more persistent effects on unemployment than standard theories can possibly explain. We develop a theory that can explain such persistence, and that is based on the distinction between insiders and outsiders in wage bargaining. We argue that if wages are largely set by bargaining between insiders and firms, shocks which affect actual unemployment tend also to affect equilibrium unemployment. We then confront the theory with both the detailed facts of the European situation as well as those of earlier periods of high persistent unemployment, such as the Great Depression in the United States.

Macroeconomic Effects of Regulation and Deregulation in Goods and Labor Markets

Product and labor market deregulation are fundamentally about reducing and redistributing rents, leading economic players to adjust in turn to this new distribution. Thus, even if deregulation eventually proves beneficial, it comes with strong distribution and dynamic effects. The transition may imply the decline of incumbent firms. Unemployment may increase for a while. Real wages may decrease before recovering, and so on. To study these issues, we build a model based on two central assumptions: Monopolistic competition in the goods market, which determines the size of rents; and bargaining in the labor market, which determines the distribution of rents between workers and firms. We then think of product market regulation as determining both the entry costs faced by firms, and the degree of competition between firms. We think of labor market regulation as determining the bargaining power of workers. Having characterized the effects of labor and product market deregulation, we then use our results to study two specific issues. First, to shed light on macroeconomic evolutions in Europe over the last twenty years, in particular on the behavior of the labor share. Second, to look at political economy interactions between product and labor market deregulation.

The Long and Large Decline in U.S. Output Volatility

The last two U.S. expansions have been unusually long. One view is that this is the result of luck, of an absence of major adverse shocks over the last twenty years. We argue that more is at work, namely a large underlying decline in output volatility. This decline is not a recent development, but rather a steady one, visible already in the 1950s and the 1960s, interrupted in the 1970s and early 1980s, with a return to trend in the late 1980s and the 1990s. The standard deviation of quarterly output growth has declined by a factor of 3 over the period. This is more than enough to account for the increased length of expansions. We reach two other conclusions. First, the trend decrease can be traced to a number of proximate causes, from a decrease in the volatility in government spending early on, to a decrease in consumption and investment volatility throughout the period, to a change in the sign of the correlation between inventory investment and sales in the last decade. Second, there is a strong relation between movements in output volatility and inflation volatility. This association accounts for the interruption of the trend decline in output volatility in the 1970s and early 1980s.

Rethinking Macroeconomic Policy

The great moderation lulled macro-economists and policymakers alike in the belief that we knew how to conduct macroeconomic policy. The crisis clearly forces to question that assessment. This paper reviews the main elements of the pre-crisis consensus, identify where we were wrong and what tenets of the pre-crisis framework still hold, and take a tentative first pass at the contours of a new macroeconomic policy framework.

Real Wage Rigidities and the New Keynesian Model

Most central banks perceive a trade-off between stabilizing inflation and stabilizing the gap between output and desired output. However, the standard new Keynesian framework implies no such trade-off. In that framework, stabilizing inflation is equivalent to stabilizing the welfare-relevant output gap. In this paper, we argue that this property of the new Keynesian framework, which we call the divine coincidence, is due to a special feature of the model: the absence of non-trivial real imperfections. We focus on one such real imperfection, namely, real wage rigidities. When the baseline new Keynesian model is extended to allow for real wage rigidities, the divine coincidence disappears, and central banks indeed face a trade-off between stabilizing inflation and stabilizing the welfare-relevant output gap. We show that not only does the extended model have more realistic normative implications, but it also has appealing positive properties. In particular, it provides a natural interpretation for the dynamic inflation-unemployment relation found in the data.

The Macroeconomic Effects of Oil Price Shocks: Why are the 2000s so Different from the 1970s?

We characterize the macroeconomics performance of a set of industrialized economies in the aftermath of the oil price shocks of the 1970s and of the last decade, focusing on the differences across episodes. We examine four different hypotheses for the mild effects on inflation and economic activity of the recent increase in the price of oil: (a) good luck (i.e. lack of concurrent adverse shocks), (b) smaller share of oil in production, (c) more flexible labor markets, and (d) improvements in monetary policy. We conclude that all four have played an important role.

Current account deficits in the Euro area : the end of the Feldstein Horioka puzzle?

Both Portugal and Greece have been running large current account deficits, and these are expected to continue in the future. Yet, financial markets do not appear to be worried. Starting from this observation, we document that Portugal and Greece are in fact representative of a broader evolution: Increasing goods and financial market integration is leading to an increasing decoupling of saving and investment within the European Union, and even more so within the Euro area. In particular, it is allowing poorer countries to invest more, save less, and run larger current account deficits. The converse holds for the richer countries.

What Do Firms Do with Cash Windfalls

Suppose that a firm receives a cash windfall which does not change its investment opportunity set, or equivalently its marginal Tobins Q. What will this firm do with the money? We provide empirical answers to this question using a sample of firms with such windfalls in the form of a won or settled lawsuit. We examine a variety of decisions of the firm to shed light on alternative theories of corporate financing and investment. Our evidence is broadly inconsistent with the perfect capital markets model. The results need to be stretched considerably to fit the asymmetric information model in which managers act in the interest of shareholders. The evidence supports the agency model of managerial behavior, in which managers try to ensure the long run survival and independence of the firms with themselves at the helm.