We contrast properties of real quantities with those of price levels and stocks of money for ten countries over the last century. Although the magnitude of output fluctuations has varied across countries and periods, relations among real quantities have been remarkably uniform. Properties of price levels, however, exhibit striking differences between periods. Inflation rates are more persistent after World War II than before, and price-level fluctuations are typically procyclical before World War II and countercyclical afterward. Fluctuations in money are less highly correlated with output in the postwar period but are no more persistent than in earlier periods.

Many view the period after the Second Industrial Revolution as a paradigm of a transition to a new economy following a technological revolution, including the Information Technology Revolution. We build a quantitative model of diffusion and growth during transitions to evaluate that view. With a learning process quantified by data on the life cycle of US manufacturing plants, the model accounts for the key features of the transition after the Second Industrial Revolution. But we find that features like those will occur in other transitions only if a large amount of knowledge about old technologies exists before the transition begins.

Are deflation and depression empirically linked? No, concludes a broad historical study of inflation and real output growth rates. Deflation and depression do seem to have been linked during the 1930s. But in the rest of the data for 17 countries and more than 100 years, there is virtually no evidence of such a link.

In this paper, we build a version of the putty-clay model in which there is a large variety of types of capital goods which are combined with energy in different fixed proportions. Our principal contribution is to establish easily checked conditions under which the problem of solving for the equilibrium of the model economy reduces to a dynamic programming problem with only two endogenous state variables, regardless of the number of different types of capital goods that are allowed. In appropriate applications, this result allows us to avoid the 'curse of dimensionality' that typically plagues attempts to analyze the dynamics of economies with a wide variety of capital goods and binding non-negativity constraints on investment. We apply these results to study the equilibrium dynamics of value-added, investment, wages, and energy use in a simple model of energy use with putty-clay capital.

We provide a theoretical interpretation of two features of international data: the countercyclical movements in net exports and the tendency for the trade balance to be negatively correlated with current and future movements in the terms of trade, but positively correlated with past movements. We document the same properties in a two-country stochastic growth model in which trade fluctuations reflect, in large part, the dynamics of capital formation. We find that our general-equilibrium perspective is essential: the relation between the trade balance and the terms of trade depends critically on the source of fluctuations.

If Exchange Rates are Random Walks, Then Almost Everything We Say About Monetary Policy is Wrong by Fernando Alvarez, Andrew Atkeson and Patrick J. Kehoe. Published in volume 97, issue 2, pages 339-345 of American Economic Review, May 2007

A common view is that bailouts of firms by governments are needed to cure inefficiencies in private markets. We propose an alternative view: even when private markets are efficient, costly bankruptcies will occur and benevolent governments without commitment will bail out firms to avoid bankruptcy costs. Bailouts then introduce inefficiencies where none had existed. Although granting the government orderly resolution powers which allow it to rewrite private contracts improves on bailout outcomes, regulating leverage and taxing size is needed to achieve the relevant constrained efficient outcome, the sustainably efficient outcome. This outcome respects governments' incentives to intervene when they lack commitment.

In recent financial crises and in recent theoretical studies of them, abrupt declines in capital inflows, or sudden stops, have been linked with large drops in output. Do sudden stops cause output drops? No, according to a standard equilibrium model in which sudden stops are generated by an abrupt tightening of a country?s collateral constraint on foreign borrowing. In this model, in fact, sudden stops lead to output increases, not decreases. An examination of the quantitative effects of a well-known sudden stop, in Mexico in the mid-1990s, confirms that a drop in output accompanying a sudden stop cannot be accounted for by the sudden stop alone. To generate an output drop during a financial crisis, as other studies have done, the model must include other economic frictions which have negative effects on output large enough to overwhelm the positive effect of the sudden stop.

Bank of Minneapolis and University of Minnesota. We thank the NSF for financial support. The views expressed herein are those of the authors and not necessarily those of the Federal Reserve Bank of Minneapolis or the Federal Reserve System. The Great Depression is not yet well understood. Economists have offered many theories for both the massive decline and the slow recovery of output during 1929—39, but no consensus has formed on the main forces behind this major economic event. Here we describe and demonstrate a simple methodology for determining which types of theories are the most promising. Several prominent theories blame the Great Depression on frictions in labor and capital markets. The sticky wage theory is that wage stickiness together with a monetary contraction produces a downturn in output. (See Michael Bordo, Christopher Erceg, and Charles Evans 2001.) The cartelization theory is that an increase in cartelization and unionization leads to a slow recovery. (See Harold Cole and Lee Ohanian 2001.) The investment friction theory is that monetary contractions increase frictions in capital markets that produce investment-driven downturns in output.

Policy-Driven Productivity in Chile and Mexico in the 1980's and 1990's by Raphael Bergoeing, Patrick J. Kehoe, Timothy J. Kehoe and Raimundo Soto. Published in volume 92, issue 2, pages 16-21 of American Economic Review, May 2002