Research Database

Previous research has suggested that discrete and occasional plant-level capital adjustments have significant aggregate implications. In particular, it has been argued that changes in plants’ willingness to invest in response to aggregate shocks can at times generate large movements in total investment demand. In this study, I re-assess these predictions in a general equilibrium environment. Specifically, assuming nonconvex costs of capital adjustment, I derive generalized (S,s) adjustment rules yielding lumpy plant-level investment within an otherwise standard equilibrium business cycle model. In contrast to previous partial equilibrium analyses, model results reveal that the aggregate effects of lumpy investment are negligible. In general equilibrium, households’ preference for relatively smooth consumption profiles offsets changes in aggregate investment demand implied by the introduction of lumpy plant-level investment. As a result, adjustments in wages and interest rates yield quantity dynamics that are virtually indistinguishable from the standard model.

Recent empirical analysis has found nonlinearities to be important in understanding aggregated investment. Using an equilibrium business cycle model, we search for aggregate nonlinearities arising from the introduction of nonconvex capital adjustment costs. We find that, while such costs lead to nontrivial nonlinearities in aggregate investment demand, equilibrium investment is effectively unchanged. Our finding, based on a model in which aggregate fluctuations arise through exogenous changes in total factor productivity, is robust to the introduction of shocks to the relative price of investment goods.

What is the force of attraction of cities? Leading explanations include the advantages of a concentrated market and knowledge spillovers. This paper develops a model of firm location decisions in which it is possible to distinguish the importance of the concentrated-market motive from other motives, including knowledge spillovers. A key aspect of the model is that it allows for the firm to choose multiple locations. The theory is applied to study the placement of manufacturing sales offices. The implications of the concentrated-market motive are found to be a salient feature of U.S. Census micro data. The structural parameters of the model are estimated. The concentrated-market motive is found to account for approximately half of the concentration of sales offices in large cities.

The central puzzle in international business cycles is that fluctuations in real exchange rates are volatile and persistent. We quantity the popular story for real exchange rate fluctuations: they are generated by monetary shocks interacting with sticky goods prices. If prices are held fixed for at least one year, risk aversion is high, and preferences are separable in leisure, then real exchange rates generated by the model are as volatile as in the data and quite persistent, but less so than in the data. The main discrepancy between the model and the data, the consumption—real exchange rate anomaly, is that the model generates a high correlation between real exchange rates and the ratio of consumption across countries, while the data show no clear pattern between these variables.

We construct a competitive model of innovation and growth under constant returns to scale. Previous models of growth under constant returns cannot model technological innovation. Current models of endogenous innovation rely on the interplay between increasing returns and monopolistic markets. In fact, established wisdom claims monopoly power to be instrumental for innovation and sees the nonrivalrous nature of ideas as a natural conduit to increasing returns. The results here challenge the positive description of previous models and the normative conclusion that monopoly through copyright and patent is socially beneficial.

We develop a parsimonious model of innovating firms rich enough to confront firm-level evidence. It captures the dynamic behavior of individual heterogenous firms, describes the evolution of an industry with simultaneous entry and exit, and delivers a general equilibrium model of technological change. While unifying the theoretical analysis of firms, industries, and the aggregate economy, the model yields insights into empirical work on innovating firms. It accounts for the persistence over time of firms’ R&D investment, the concentration of R&D among incumbent firms, and the link between R&D and patenting. Furthermore, it explains why R&D as a fraction of revenues is strongly related to firm productivity yet largely unrelated to firm size or growth.

We study a simple model of factor saving technological innovation in a concave framework. Capital can be used either to reproduce itself or, at additional cost, to produce a higher quality of capital that requires less labor input. If higher quality capital can be produced quickly, we get a model of exogenous balanced growth as a special case. If, however, higher quality capital can be produced slowly, we get a model of endogenous growth in which the growth rate of the economy and the rate of adoption of new technologies are determined by preferences, technology, and initial conditions. Moreover, in the latter case, the process of growth is necessarily uneven, exhibiting a natural cycle with alternating periods of high and low growth. Growth paths and technological innovations also exhibit dependence upon initial conditions. The model provides a step toward a theory of endogenous innovation under conditions of perfect competition.

Does national market size matter for industrial structure? Round One (Krugman) answered in the affirmative: Home market effects matter. Round Two (Davis) refuted this, arguing that an assumption of convenience—transport costs only for the differentiated goods—conveniently obtained the result. In Round Three we relax another persistent assumption of convenience—two industry types differentiated only by the degree of scale economies—and find that market size reemerges as a relevant force in determining industrial structure.

We study decentralized learning in organizations. Decentralization is captured through a symmetry constraint on agents’ strategies. Among such attainable strategies, we solve for optimal and equilibrium strategies. We model the organization as a repeated game with imperfectly observable actions. A fixed but unknown subset of action profiles are successes and all other action profiles are failures. The game is played until either there is a success or the time horizon is reached. For any time horizon, including infinity, we demonstrate existence of optimal attainable strategies and show that they are Nash equilibria. For some time horizons, we can solve explicitly for the optimal attainable strategies and show uniqueness. The solution connects the learning behavior of agents to the fundamentals that characterize the organization: Agents in the organization respond more slowly to failure as the future becomes more important, the size of the organization increases and the probability of success decreases.

Central to ongoing debates over the desirability of monetary unions is a supposed trade-off, outlined by Mundell [1961]: a monetary union reduces transactions costs but renders stabilization policy less effective. If shocks across countries are sufficiently correlated, then, according to this argument, delegating monetary policy to a single central bank is not very costly and a monetary union is desirable.

This paper explores this argument in a setting with both monetary and fiscal policies. In an economy with monetary policy alone, we confirm the presence of the trade-off and find that indeed a monetary union will not be welfare improving if the correlation of national shocks is too low. However, fiscal interventions by national governments, combined with a central bank that has the ability to commit to monetary policy, overturn these results. In equilibrium, such a monetary union will be welfare improving for any correlation of shocks.

Previous work has had difficulty generating household saving behavior that makes the distribution of wealth much more concentrated than that of labor earnings, and that makes the richest households hold onto large amounts of wealth, even during very old age. I construct a quantitative, general equilibrium, overlapping-generations model in which parents and children are linked by accidental and voluntary bequests and by earnings ability. I show that voluntary bequests can explain the emergence of large estates, while accidental bequests alone cannot, and that adding earnings persistence within families increases wealth concentration even more. I also show that the introduction of a bequest motive generates lifetime savings profiles more consistent with the data.

Herd behavior is argued by many to be present in many markets. Existing models of such behavior have been subjected to two apparently devastating critiques. The continuous investment critique is that in the basic model herds disappear if simple zero-one investment decisions are replaced by the more appealing assumption that investment decisions are continuous. The price critique is that herds disappear if, as seems natural, other investors can observe asset market prices. We argue that neither critique is devastating. We show that once we replace the unappealing exogenous timing assumption of the early models that investors move in a pre-specified order by a more appealing endogenous timing assumption that investors can move whenever they choose then herds reappear.

How should a government use the power to commit to ensure a desirable equilibrium outcome? In this paper, I show a misleading aspect of what has become a standard approach to this question, and I propose an alternative. I show that the complete description of an optimal (indeed, of any) policy scheme requires outlining the consequences of paths that are often neglected. The specification of policy along those paths is crucial in determining which schemes implement a unique equilibrium and which ones leave room for multiple equilibria that depend on the expectations of the private sector.

Are optimal monetary and fiscal policies time consistent in a monetary economy? Yes, but if and only if under commitment the Friedman rule of setting nominal interest rates to zero is optimal. This result is of applied interest because the Friedman rule is optimal for the standard preferences used in applied work, those consistent with the growth facts.

This paper proposes a simple method for guiding researchers in developing quantitative models of economic fluctuations. We show that a large class of models, including models with various frictions, are equivalent to a prototype growth model with time-varying wedges that, at least at face value, look like time-varying productivity, labor taxes, and capital income taxes. We label the time-varying wedges as efficiency wedges, labor wedges, and investment wedges. We use data to measure these wedges and then feed them back into the prototype growth model. We then assess the fraction of fluctuations accounted for by these wedges during the great depressions of the 1930s in the United States, Germany, and Canada. We find that the efficiency and labor wedges in combination account for essentially all of the declines and subsequent recoveries. Investment wedges play, at best, a minor role.

Previous literature has shown that the study and characterization of constrained efficient allocations in economies with limited enforcement is useful to understand the limited risk sharing observed in many contexts, in particular between sovereign countries. In this paper we show that these constrained efficient allocations arise as equilibria in an economy in which private agents behave competitively, taking as given a set of taxes. We then show that these taxes, which end up limiting risk sharing, arise as an equilibrium of a dynamic game between governments. Our decentralization is different from the existing ones proposed in the literature. We find it intuitively appealing and we think it goes farther than the existing literature in endogenizing the primitive forces that lead to a lack of risk sharing in equilibrium.

How much discretion is it optimal to give the monetary authority in setting its policy? We analyze this mechanism design question in an economy with an agreed-upon social welfare function that depends on the randomly fluctuating state of the economy. The monetary authority has private information about that state. In the model, well-designed rules trade off society’s desire to give the monetary authority flexibility to react to its private information against society’s need to guard against the standard time inconsistency problem arising from the temptation to stimulate the economy with unexpected inflation. We find that the optimal degree of monetary policy discretion is decreasing in the severity of the time inconsistency problem. As this problem becomes sufficiently severe, the optimal degree of discretion is none at all. We also find that, despite the apparent complexity of this dynamic mechanism design problem, society can implement the optimal policy simply by legislating an inflation cap that specifies the highest allowable inflation rate.

Both Chile and Mexico experienced severe economic crises in the early 1980s, yet Chile recovered much faster than Mexico. This study analyzes four possible explanations for this difference and rules out three, explanations based on money supply expansion, real wage and real exchange rate declines, and foreign debt overhangs. The fourth explanation is based on government policy reforms in the two countries. Using growth accounting and a calibrated growth model, the study determines that the only policy reforms promising as explanations are those that primarily affect total factor productivity, or how inputs are used, not the inputs themselves. Interpreting historical evidence with economic theory, the study concludes that the crucial difference between Chile and Mexico in the 1980s and 1990s is earlier government policy reforms in Chile, particularly reforms in policies affecting the banking system and bankruptcy procedures.

This article uses data from the 1998 Survey of Consumer Finances and from recent waves of the Panel Study of Income Dynamics to update a study of economic inequality in the United States based on 1992 and earlier data. The article reports data on the U.S. distributions of earnings, income, and wealth and on related features of inequality, such as age, employment status, educational attainment, and marital status. It also reports data on the economic inequality among U.S. households in financial trouble and on the economic mobility of U.S. households. The article finds that earnings, income, and wealth were very unequally distributed among U.S. households late in the 1990s, just as they had been at the beginning of the decade. It concludes that the basic facts about economic inequality in the United States did not change much during the 1990s.

This article describes a debate about the validity of the quantity theory of money and offers further evidence against it. The evidence is primarily from the North American colonies of Virginia, New York, and Pennsylvania and regards the issue of measuring the money supply. Studies have shown that changes in colonial money and inflation are inconsistent with the quantity theory. Some have argued that those studies measure money wrong: specie belongs in the measure because the colonies were on a fixed exchange rate system with Britain; changes in colonial paper money were offset by specie flows. When specie is counted, the quantity theory stands. This study responds with evidence that the critics are wrong: the colonies had no such fixed exchange rate regime, and movements in the stock of colonial paper currency cannot have been offset by specie flows.

This study uses John Rawls’ behind-the-veil of ignorance device as a fairness criterion to evaluate social policies and applies it to a contracting model in which the terms equality of opportunity and equality of result are well defined. The results suggest that fairness and inequality—even extreme inequality—are compatible. In a static world, when incentives must be provided, fairness implies equality of opportunity, but inequality of result. In a dynamic world of long-lived individuals, fairness implies not only inequality of result, but also, eventually, infinite inequality of result. If each period of the dynamic model is interpreted as a generation, then eventual infinite inequality holds for opportunity as well, as long as fairness is from the perspective of the first generation. If preferences of later generations are taken into account, then inequality of opportunity still occurs, although not at extreme levels.

A classic example of a privately created interbank payments system was operated by the Suffolk Bank of New England (1825–58). Known as the Suffolk Banking System, it was the nation’s first regionwide net-clearing system for bank notes. While it operated, notes of all New England banks circulated at par throughout the region. Some have concluded from this experience that unfettered competition in the provision of payments services can produce an efficient payments system. But another look at the history of the Suffolk Banking System questions this conclusion. The Suffolk Bank earned extraordinary profits, and note-clearing may have been a natural monopoly. There is no consensus in the literature about whether unfettered operation of markets with natural monopolies produces an efficient allocation of resources.

This study was originally published in the St. Louis Federal Reserve Bank’s Review (May/June 1998, vol. 80, no. 3, pp. 105–16).

This article argues that the quantity theory of money is not supported by the evidence. Contrary to the quantity theory, the article says, the value of money depends primarily on how carefully it is backed. That is, the rate of inflation depends more on underlying fiscal policies than on rates of money growth. The evidence for this argument comes from a close look at the way in which the colony of Massachusetts ended a severe long-term inflation in 1750. Other British North American colonies endured similar episodes, all of which parallel some periods of severe inflation in the 20th century United States. The 18th century evidence thus contains lessons for modern monetary policy.

This study assesses five common explanations for the large decline in U.S. total factor productivity (TFP) during the Great Depression: changes in capacity utilization, factor input quality, and production composition; labor hoarding; and increasing returns to scale. The study finds that these factors explain less than one-third of the 18 percent TFP decline between 1929 and 1933. The rest of the decline remains unexplained. The study offers a potential explanation: declines in organization capital, the knowledge firms use to organize production, caused by breakdowns in relationships between firms and their suppliers, for example. As some firms failed during the Depression, efficiency in surviving firms decreased; managers had to shift time away from production in order to establish new relationships, and firms had to shift to unfamiliar technologies that initially were operated inefficiently.