Research Database

We examine the conditions under which steady states with low real interest rates—real rates substantially below the output growth rate—exist in an overlapping generations model with production, capital accumulation, a labor-leisure trade-off, technological progress, and agents who live for many periods. The number of periods in an agent's life (n) is left open for much of the analysis and determines the temporal interpretation of a time period. The qualitative properties of the model are largely invariant to different values of n. We find that two low real interest rate steady states exist for empirically plausible values of the parameters of the model. Outside liabilities such as fiat currency or unbacked government debt are valued in one of these steady states.

Different monetary aggregates covary very differently with short term nominal interest rates. Broad monetary aggregates like Ml and the monetary base covary positively with current and future values of short term interest rates. In contrast, the nonborrowed reserves of banks covary negatively with current and future interest rates. Observations like this 'sign switch' lie at the core of recent debates about the effects of monetary policy actions on short term interest rates. This paper develops a general equilibrium monetary business cycle model which is consistent with these facts. Our basic explanation of the 'sign switch' is that movements in nonborrowed reserves are dominated by exogenous shocks to monetary policy, while movements in the base and Ml are dominated by endogenous responses to non-policy shocks.

We study a variant of the one-sector neoclassical growth model of Diamond in which capital investment must be credit financed, and an adverse selection problem appears in loan markets. The result is that the unfettered operation of credit markets leads to a one-dimensional indeterminacy of equilibrium. Many equilibria display economic fluctuations which do not vanish asymptotically; such equilibria are characterized by transitions between a Walrasian regime in which the adverse selection problem does not matter, and a regime of credit rationing in which it does. Moreover, for some configurations of parameters, all equilibria display such transitions for two reasons. One, the banking system imposes ceilings on credit when the economy expands and floors when it contracts because the quality of public information about the applicant pool of potential borrowers is negatively correlated with the demand for credit. Two, depositors believe that returns on bank deposits will be low (or high): these beliefs lead them to transfer savings out of (into) the banking system and into less (more) productive uses. The associated disintermediation (or its opposite) causes banks to contract (expand) credit. The result is a set of equilibrium interest rates on loans that validate depositors' original beliefs. We investigate the existence of perfect foresight equilibria displaying periodic (possibly asymmetric) cycles that consist of m periods of expansion followed by n periods of contraction, and propose an algorithm that detects all such cycles.

In this paper a dynamic model is constructed in which labor and capital taxes are determined endogenously through majority voting. The wealth distribution of the economy is shown to influence the voting behavior, and hence the equilibrium levels of the tax rates, which in turn affect the future distribution of wealth. It is shown that the economy exhibits a unique dynamic behavior. Because of the endogenously determined taxes, the asset prices, wealth distribution, and the tax rates can display persistent fluctuations, and even limit cycles, in reaction to exogenous disturbances, or even due to initial conditions. It is also shown that "tax smoothing" does not necessarily appear to naturally arise in such a model, as the economy can display extreme fluctuations in the endogenously determined tax rates.

A cash-in-advance model with sequential markets is constructed, where unanticipated monetary injections are nonneutral and can potentially produce large liquidity effects. However, if the monetary authority adheres to an optimal money rule, money should not respond to unanticipated shocks, so that a Friedman rule is suboptimal and the monetary authority does not exploit the liquidity effect. Quantitatively, the model can generate variability in money and nominal interest rates close to what is observed, and can produce data with no obvious evidence of the existence of liquidity effects.

I show that a simple sticky price model based on Rotemberg (1982) is consistent with a variety of facts concerning the correlation of prices, hours and output. In particular, I show that it is consistent with a negative correlation between the detrended levels of output and prices when the Beveridge-Nelson method is used to detrend both the price and output data. Such a correlation, i.e.,a negative correlation between the predictable movements in output and the predictable movements in prices is present (and very strong) in U.S. data. Consistent with the model, this correlation is stronger than correlations between prices and hours of work. I also study the size of the predictable price movements that are associated with predictable output movements as well as the degree to which there are predictable movements in monetary aggregates associated with predictable movements in output. These facts are used to shed light on the degree to which the Federal Reserve has pursued a policy designed to stabilize expected inflation.

We examine price formation in a simple static model with asymmetric information, a countable number of risk neutral traders and without noise traders. Prices can exhibit excess volatility (the variance of prices exceeds the variance of dividends), even in such a simple model. More generally, we show that for an open set of parameter values no equilibrium has prices which turn out to equal the value of dividends state by state, while for another open set of parameter values there exist equilibria such that equilibrium prices equal the value of dividends state by state. When information collection is endogenous and costly, expected prices exhibit a "V-shape" as a function of the cost of information: They are maximized when information is either costless so that everyone acquires it, or else is so costly that no one chooses to acquire it. Prices are depressed if information is cheap enough so that some agents become informed, while others do not. If the model is altered so that information is useful in making productive decisions, then the V-shape is altered, reducing the attractiveness of prohibitively high costs.

This paper develops a dynamic model of general imperfect competition by embedding the Shapley-Shubik model of market games into an overlapping generations framework. Existence of an open market equilibrium where there is trading at each post is demonstrated when there are an arbitrary (finite) number of commodities in each period and an arbitrary (finite) number of consumers in each generation. The open market equilibria are fully characterized when there is a single consumption good in each period and it is shown that stationary open market equilibria exist if endowments are not Pareto optimal. Two examples are also given. The first calculates the stationary equilibrium in an economy, and the second shows that the on replicating the economy the stationary equilibria converge to the unique non-autarky stationary equilibrium in the corresponding Walrasian overlapping generations economy. Preliminary on-going work indicates the possibility of cycles and other fluctuations even in the log-linear economy.

A cash-in-advance model with sequential markets is constructed, where unanticipated monetary injections are nonneutral and can potentially produce large liquidity effects. However, if the monetary authority adheres to an optimal money rule, money should not respond to unanticipated shocks, so that a Friedman rule is suboptimal and the monetary authority does not exploit the liquidity effect. Quantitatively, the model can generate variability in money and nominal interest rates close to what is observed, and can produce data with no obvious evidence of the existence of liquidity effects.

We formulate a representative consumer model of intertemporal resource reallocation in which fluctuations in equity prices contribute to the smoothing of consumption flows. Features of the model include (a) an incompletely observable stochastic process of productivity shocks leading to fluctuating confidence of beliefs and (b) technologies involving commitments of a resource good. These features are exploited to show that (1) equities are not a representative form of total wealth and (2) the valuation of currently active firms is not representative of the valuation of all firms. We examine the implications of (1) and (2) to argue that empirical findings for the volatility and 'value shortfall' of equity prices may be consistent with a frictionless representative consumer model having a low degree of risk-aversion. Simulation of a calibrated version of the model for a risk-neutral consumer shows that when the 'data' is analyzed according to current econometric procedures, it is found to exhibit volatility of the same order of magnitude as that found in the actual data, although the model contains no excess volatility.

Over the past decade, a substantial literature on the estimation of discrete choice dynamic programming (DC-DP) models of behavior has developed. However, this literature now faces major computational barriers. Specifically, in order to solve the dynamic programming (DP) problems that generate agents' decision rules in DC-DP models, high dimensional integrations must be performed at each point in the state space of the DP problem. In this paper we explore the performance of approximate solutions to DP problems. Our approximation method consists of: 1) using Monte Carlo integration to simulate the required multiple integrals at a subset of the state points, and 2) interpolating the non-simulated values using a regression function. The overall performance of this approximation method appears to be excellent, both in terms of the degree to which it mimics the exact solution, and in terms of the parameter estimates it generates when embedded in an estimation algorithm.

Standard models of public education provision predict an implicit transfer of resources from higher income individuals toward lower income individuals. Many studies have documented that public higher education involves a transfer in the reverse direction. We show that this pattern of redistribution is an equilibrium outcome in a model in which education is only partially publicly provided and individuals vote over the extent to which it is subsidized. We show that increased inequality in the income distribution makes this outcome more likely and that the efficiency implications of this exclusion depend on the wealth of the economy.

A standard explanation for why sovereign governments repay their debts is that they must maintain a good reputation to easily borrow more. We show that the ability of reputation to support debt depends critically on the assumptions made about institutions. At one extreme, we assume that bankers can default on payments they owe to governments. At the other, we assume that bankers are committed to honoring contracts made with governments. We show that if bankers can default, then a government gets enduring benefits from maintaining a good relationship with bankers and its reputation can support a large amount of borrowing. If, however, bankers must honor their contracts, then a government gets only transient benefits from maintaining a good relationship and its reputation can support zero borrowing.

We report on experiments that tested the predictions of competing theories of learning in games. Experimental subjects played a version of the three-person matching-pennies game. The unique mixed-strategy Nash equilibrium of this game is locally unstable under naive Bayesian learning. Sophisticated Bayesian learning predicts that expectations will converge to Nash equilibrium if players observe the entire history of play. Neither theory requires payoffs to be common knowledge. We develop maximum-likelihood tests for the independence conditions implied by the mixed-strategy Nash equilibrium. We find that perfect monitoring was sufficient and complete payoff information was unnecessary for average play to be consistent with the equilibrium (as is predicted by sophisticated Bayesian learning). When subjects had imperfect monitoring and incomplete payoff information, average play was inconsistent with the equilibrium.

Why are methods of production used in an area when more “efficient” methods are available? This paper explores a “resistance to technology” explanation. In particular, the paper attempts to understand why some industries, like the construction industry, have had continued success in blocking new methods, while others have met failure, like the dairy industry's recent attempt to block bST. We develop a model which shows that how easily goods move between areas determines in part the extent of resistance to new methods in an area.

Dynamic general equilibrium models that include explicit household production sectors provide a useful framework within which to analyze a variety of macroeconomic issues. However, some implications of these models depend critically on parameters, including the elasticity of substitution between market and home consumption goods, about which there is little information in the literature. Using the PSID, we estimate these parameters for single males, single females, and married couples. At least for single females and married couples, the results indicate a high enough substitution elasticity that including home production will make a significant difference in applied general equilibrium theory.

Statistical inference in multinomial multiperiod probit models has been hindered in the past by the high dimensional numerical integrations necessary to form the likelihood functions, posterior distributions, or moment conditions in these models. We describe three alternative approaches to inference that circumvent the integration problem: Bayesian inference using Gibbs sampling and data augmentation to compute posterior moments, simulated maximum likelihood (SML) estimation using the GHK recursive probability simulator, and method of simulated moment (MSM) estimation using the GHK simulator. We perform a set of Monte-Carlo experiments to compare the performance of these approaches. Although all the methods perform reasonably well, some important differences emerge. The root mean square errors (RMSEs) of the SML parameter estimates around the data generating values exceed those of the MSM estimates by 21 percent on average, while the RMSEs of the MSM estimates exceed those of the posterior parameter means obtained via agreement via Gibbs sampling by 18 percent on average. While MSM produces a good agreement between empirical RMSEs and asymptotic standard errors, the RMSEs of the SML estimates exceed the asymptotic standard errors by 28 percent on average. Also, the SML estimates of serial correlation parameters exhibit significant downward bias.

This paper catalogues formulas that are useful for estimating dynamic linear economic models. We describe algorithms for computing equilibria of an economic model and for recursively computing a Gaussian likelihood function and its gradient with respect to parameters. We display an application to Rosen, Murphy, and Scheinkman's (1994) model of cattle cycles.

This paper develops a simple model of sovereign debt in which defaulting nations are excluded from capital markets and regain access by making partial repayments. This is consistent with the historical evidence that defaulting countries return to international loan markets soon after a settlement, but after varying periods of exclusion.

We consider a dynamic, stochastic equilibrium business cycle model which is augmented to reflect seasonal shifts in preferences, technology, and government purchases. Our estimated parameterization implies implausibly large seasonal variation in the state of technology: rising at an annual rate of 24% in the fourth quarter and falling at an annual rate of 28% in the first quarter. Furthermore, our findings indicate that variation in the state of technology of this magnitude is required if the model is to explain the main features of the seasonal cycle.

This study examines common stock prices around ex-dividend dates. Such price data usually contain a mixture of observations—some with and some without arbitrageurs and/or dividend capturers active. Our theory predicts that such mixing will result in some nonlinear relation between percentage price drop and dividend yield—not the commonly assumed linear relation. This prediction and another important prediction of theory are supported empirically. In a variety of tests, marginal price drop is not significantly different from the dividend amount. Thus, over the last several decades, one-for-one marginal price drop has been an excellent (average) rule of thumb.

We integrate search theory into an equilibrium framework in a new way and argue that the result is a simple but powerful tool for understanding many issues related to bilateral matching. We assume for much of what we do that utility is less than perfectly transferable. This turns out to generate multiple equilibria that do not arise in a standard model, with transferable utility, unless one adds increasing returns. We also provide simple conditions for uniqueness that apply to models with or without transferable utility or increasing returns. Examples, applications, and extensions are discussed.

This research compares several approaches to inference in the multinomial probit model, based on Monte-Carlo results for a seven choice model. The experiment compares the simulated maximum likelihood estimator using the GHK recursive probability simulator, the method of simulated moments estimator using the GHK recursive simulator and kernel-smoothed frequency simulators, and posterior means using a Gibbs sampling-data augmentation algorithm. Each estimator is applied in nine different models, which have from 1 to 40 free parameters. The performance of all estimators is found to be satisfactory. However, the results indicate that the method of simulated moments estimator with the kernel-smoothed frequency simulator does not perform quite as well as the other three methods. Among those three, the Gibbs sampling-data augmentation algorithm appears to have a slight overall edge, with the relative performance of MSM and SML based on the GHK simulator difficult to determine.

In this paper we develop alternative ways to compare asset pricing models when it is understood that their implied stochastic discount factors do not price all portfolios correctly. Unlike comparisons based on chi-squared statistics associated with null hypotheses that models are correct, our measures of model performance do not reward variability of discount factor proxies. One of our measures is designed to exploit fully the implications of arbitrage-free pricing of derivative claims. We demonstrate empirically the usefulness of methods in assessing some alternative stochastic factor models that have been proposed in asset pricing literature.

According to previous studies, the demand-liability feature of national bank notes did not present a problem for note-issuing banks because the nonbank public treated notes and other currency as perfect substitutes. However, that view, when combined with nonbindingness of the collateral restriction against note issue, itself an implication of the fact that some eligible collateral was not used for that purpose, implies that the safe short-term interest rate is pegged at the tax rate on note circulation. Since evidence on short-term interest rates is inconsistent with such a peg, that view must be rejected.

We describe several methods for approximating the solution to a model in which inequality constraints occasionally bind, and we compare their performance. We apply the methods to a particular model economy which satisfies two criteria: It is similar to the type of model used in actual research applications, and it is sufficiently simple that we can compute what we presume is virtually the exact solution. We have two results. First, all the algorithms are reasonably accurate. Second, on the basis of speed, accuracy and convenience of implementation, one algorithm dominates the rest. We show how to implement this algorithm in a general multidimensional setting, and discuss the likelihood that the results based on our example economy generalize.

Applied general equilibrium models with imperfect competition and economies of scale have been extensively used for analyzing international trade and development policy issues. They offer a natural framework for testing the empirical relevance of propositions from the industrial organization and new trade theoretical literature. This paper warns model builders and users that considerable caution is needed in interpreting the results and deriving strong policy conclusions from these models: in this generation of applied general equilibrium models, nonuniqueness of equilibria is not a theoretical curiosum, but a potentially serious problem. Disregarding this may lead to dramatically wrong policy appraisals.

An economic experiment consists of the act of placing people in an environment desired by the experimenter, who then records the time paths of their economic behavior. Performing experiments that use actual people at the level of national economies is obviously not practical, but constructing a model economy and computing the economic behavior of the model’s people is. We refer to such experiments as computational experiments because the economic behavior of the model’s people is computed. In this essay, we specify the steps in designing a computational experiment to address some well posed quantitative question. We emphasize that the computational experiment is an econometric tool used in the task of deriving the quantitative implications of theory.

The goal of this paper is to extend the analysis of strategic bargaining to nonstationary environments, where preferences or opportunities may be changing over time. We are mainly interested in equilibria where trade occurs immediately, once the agents start negotiating, but the terms of trade depend on when the negotiations begin. We characterize equilibria in terms of simply dynamical systems, and compare these outcomes with the myopic Nash bargaining solution. We illustrate the practicality of the approach with an application in monetary economics.

This article contends that the various measures of the contribution of technology shocks to business cycles calculated using the real business cycle modeling method are not corroborated. The article focuses on a different and much simpler method for calculating the contribution of technology shocks, which takes account of facts concerning the productivity/labor input correlation and the variability of labor input relative to output. Under several standard assumptions, the method predicts that the contribution of technology shocks must be large (at least 78 percent), that the labor supply elasticity need not be large to explain the observed fluctuation in labor input, and that the contribution of technology shocks can be estimated fairly precisely. The method also estimates that the contribution of technology shocks could be lower than 78 percent under alternative assumptions.

This article is a progress report on research that attempts to include one type of market incompleteness and frictions in macroeconomic models. The focus of the research is the absence of insurance markets in which individual-specific risks may be insured against. The article describes some areas where this type of research has been and promises to be particularly useful, including consumption and saving, wealth distribution, asset markets, business cycles, and fiscal policies. The article also describes work in each of these areas that was presented at a conference sponsored by the Federal Reserve Bank of Minneapolis in the fall of 1993.

This paper studies the outcome of fully insured random selections among multiple competitive equilibria. This defines an iterative procedure of reallocation which is Pareto improving at each step. The process converges to a unique Pareto optimal allocation in finitely many steps. The key requirement is that random selections be continuous, which is a generic condition for smooth exchange economies with strictly concave utility functions.

It is often argued that with a positively skewed income distribution (median less than mean) a majority voting over proportional tax rates would result in higher tax rates than those that maximize average welfare, and will accordingly reduce aggregate savings. We reexamine this view in a capital accumulation model, in which distorting redistributive taxes provide insurance against idiosyncratic shocks, and income distributions evolve endogenously. We find small differences of either sign between the tax rates set by a majority voting and a utilitarian government, for reasonable parametric specifications. We show how these differences reflect a greater responsiveness of a utilitarian government to the average need for the insurance provided by the tax-redistribution scheme. These conclusions remain true despite the fact that the model simulations produce positively skewed distributions of total income across agents.

We describe a model for calculating the optimal quantity of debt and then apply it to the U.S. economy. The model consists of a large number of infinitely-lived households whose saving behavior is influenced by precautionary saving motives and borrowing constraints. This model incorporates a different role for government debt than the standard representative agent growth model and captures different trade-offs between the benefits and costs of varying its level. Government debt enhances the liquidity of households by providing additional assets for smoothing consumption (in addition to claims to capital) and effectively loosening borrowing constraints. By raising the interest rate, government debt makes assets less costly to hold and more effective in smoothing consumption. However, the implied taxes have wealth distribution, incentive, and insurance effects. Further, government debt crowds out capital (via higher interest rates) and lowers per capita consumption. Our quantitative analysis suggests that the crowding out effect is decisive for welfare. We also describe variations of the model which permit endogenous growth. It turns out that even with lump sum taxes and inelastic labor, government debt as well as government consumption have growth rate effects, thereby implying large welfare gains from reducing the level of debt.

The money demand literature presents much conflicting evidence on this question. For example, Lucas (1988) reports unrestricted money demand regressions which seem to imply that long-run money demand elasticities are highly unstable across subsamples. At the same time, he also presents evidence from money demand regressions with the income elasticity restricted to unity which seem to suggest stability. We conduct a formal analysis which weighs these apparently conflicting facts to determine which hypothesis is more plausible; the hypothesis that money demand is stable, or the hypothesis that money demand is unstable. We find that the stability hypothesis is the more plausible one. Thus, according to our data set, the answer to the question in the title is "yes".

This paper reexamines the conventional wisdom that commercial banking is an industry in severe decline. We find that a careful reading of the evidence does not justify this conclusion. It is true that on-balance sheet assets held by commercial banks have declined as a share of total intermediary assets. But this measure overstates any drop in banking, for three reasons. First, it ignores the rapid growth in commercial banks' off-balance sheet activities. Second, it fails to take account of the substantial growth in off-shore C&I lending by foreign banks. Third, it ignores the fact that over the last several decades financial intermediation has grown rapidly relative to the rest of the economy. We find that after adjusting the measure of bank assets to account for these considerations there is no clear evidence of secular decline. To corroborate these findings, we also construct an alternative measure of the importance of banking, using data from the National Income Accounts. Again, we find no clear evidence of a sustained declined. At most the industry may have suffered a slight loss of market share over the last decade. But as we discuss, this loss may reflect a transitory response to a series of adverse shocks and the phasing in of new regulatory requirements, rather than the beginning of a permanent decline.

This paper integrates and extends some recent computational advances in Bayesian inference with the objective of more fully realizing the Bayesian promise of coherent inference and model comparison in economics. It combines Markov chain Monte Carlo and independence Monte Carlo with importance sampling to provide an efficient and generic method for updating posterior distributions. It exploits the multiplicative decomposition of marginalized likelihood into predictive factors, to compute posterior odds ratios efficiently and with minimal further investment in software. It argues for the use of predictive odds ratios in model comparison in economics. Finally, it suggests procedures for public reporting that will enable remote clients to conveniently modify priors, form posterior expectations of their own functions of interest, and update the posterior distribution with new observations. A series of examples explores the practicality and efficiency of these methods.

We construct a vintage capital model of economic growth in which the decision to replace old technologies with new ones is modeled explicitly. Depreciation in this environment is an economic, not a physical concept. We describe the balanced growth paths and the transitional dynamics of this economy. We illustrate the importance of vintage capital by analyzing the response of the economy to fiscal policies designed to stimulate investment in new technologies.

This study examines common stock prices around ex-dividend dates. Such price data usually contain a mixture of observations—some with and some without arbitrageurs and/or dividend capturers active. Our theory predicts that such mixing will result in a nonlinear relation between percentage price drop and dividend yield—not the commonly assumed linear relation. This prediction and another important prediction of theory are supported empirically. In a variety of tests, marginal price drop is not significantly different from the dividend amount. Thus, over the last several decades, one-for-one marginal price drop has been an excellent (average) rule of thumb.

In 1985–86 the authors were members of a team that constructed a static applied general equilibrium model that was used to analyze the impact on the Spanish economy of the 1986 fiscal reform, which accompanied Spain’s entry into the European Community. This paper compares the results obtained to recently published data for 1985–87; we find that the model performed well in predicting the changes in relative prices and resource allocation that actually occurred, particularly if we incorporate exogenous shocks that affected the Spanish economy in 1986. We also analyze the sensitivity of the results to alternative specifications of the labor market and macroeconomic closure rules; we find that the central results are robust.

For a wide class of dynamic models, Chamley (1986) has shown that the optimal capital income tax rate is zero in the long run. Lucas (1990) has argued that for the U.S. economy there is a significant welfare gain from switching to this policy. We show that for the Bewley (1986) class of models with heterogeneous agents and incomplete markets (due to uninsured idiosyncratic shocks), and borrowing constraints the optimal tax rate on capital income is positive even in the long run. Quantitative analysis of a parametric version of such a model suggests that one cannot dismiss the possibility that the observed tax rates on capital and labor income for the U.S. economy are fairly close to being (long run) optimal. We also provide an existence proof for the dynamic Ramsey optimal tax problem in this environment.

In the specification of linear regression models it is common to indicate a list of candidate variables from which a subset enters the model with nonzero coefficients. This paper interprets this specification as a mixed continuous-discrete prior distribution for coefficient values. It then utilizes a Gibbs sampler to construct posterior moments. It is shown how this method can incorporate sign constraints and provide posterior probabilities for all possible subsets of regressors. The methods are illustrated using some standard data sets.

This paper studies the empirical performance of stochastic volatility models for twenty years of weekly exchange rate data. We concentrate on the effects of the distribution of the exchange rate innovations for parameter estimates and for estimates of the latent volatility series. We approximate the density of the log of exchange rate innovations by a mixture of normals. The major findings of the paper are that: (1) explicitly incorporating fat-tailed innovations increases the estimates of the persistence of volatility dynamics; (ii) estimates of the latent volatility series depend strongly on the estimation technique; (iii) the estimation error of the volatility time series is so large that finance applications to option pricing should be interpreted with care. We reach these conclusions using three different estimation techniques: quasi maximum likelihood, simulated EM, and a Bayesian procedure based on the Gibbs sampler.

This paper develops the Parameterized Expectations Approach (PEA) for solving nonlinear dynamic stochastic models with rational expectations. The method can be applied to a variety of models, including models with strong nonlinearities, sub-optimal equilibria, and many continuous state variables. In this approach, the conditional expectations in the equilibrium conditions are approximated by finite-dimensional classes of functional forms. The approach is highly efficient computationally because it incorporates endogenous oversampling and Monte-Carlo integration, and it does not impost a discrete grid on the state variables or the stochastic shocks. We prove that PEA can approximate the correct solution with arbitrary accuracy on the ergodic set by increasing the size of the Monte-Carlo simulations and the dimensionality of the approximating family of functions.

Three key features of the employment process in the U.S. economy are that job creation is procyclical, job destruction is countercyclical, and job creation is less volatile than job destruction. These features are also found at the sectoral (goods and services) level. The paper develops, calibrates, and simulates a two sector general equilibrium model including both aggregate and sectoral shocks. The behavior of the model economy mimics the job creation and destruction facts. Sectoral shocks play a significant role in determining the aggregate level of nonemployment.

This article reexamines the conventional wisdom that commercial banking is in severe decline. A careful reading of the evidence does not support it. True, on-balance sheet assets held by commercial banks have declined as a share of total intermediary assets. But this measure ignores the substantial growth in banks' off-balance sheet activities, in off-shore lending by foreign banks, and in the size of the financial intermediation sector. Adjusted for these considerations, the bank-assets measure shows no clear evidence of secular decline. Neither does an alternative measure, constructed using data from the national income accounts. At most, banking may have suffered a slight loss of market share lately. But this loss is a temporary response to a series of adverse shocks rather than the start of a permanent decline.

This article argues that the poor performance of the U.S. banking industry in the 1980s was due mainly to the risk-taking of the largest banks, which was encouraged by the U.S. government's too-big-to-fail policy. The article documents the recent trend toward riskier bank portfolios and the corresponding decline in bank profitability. A breakdown of the data by location and by asset size reveals that bank problems were concentrated in areas with troubled industries (oil, real estate, and agriculture) and among banks with the largest assets. In a statistical study controlling for location, asset size remains a significant factor in bank performance. The article concludes with a rough quantitative estimate of the cost to the industry of the poor performance of large banks.

We analyze a real business cycle model in which the government optimally chooses public investment and nonmilitary current expenditures, to maximize the welfare of the representative private agent. We characterize the optimal response of endogenous spending to shocks to technology and to military expenditures. Comovements between the components of government spending and other macroeconomic aggregates predicted by the model are compared with the corresponding comovements in the U.S. data. The model captures the qualitative features of the relative volatilities of the components of government spending quite well, but predicts too high correlations between the components of government spending and output.

In this paper, we describe and analyze the basic structure of the applied general equilibrium (AGE) models used to assess the effects of government trade policies. Once we have constructed the basic model, we extend it to cover features such as increasing returns to scale, imperfect competition, and differentiated products, following the AGE modeling trend of the past 10 years. We then compare a static AGE model's predictions with the actual data on how Spain was affected by entering the European Community and find that, when exogenous effects are included, a static AGE model's predictions are fairly accurate.

We describe the postwar U.S. business cycle for the durable and nondurable goods producing sector. The business cycle is characterized by positive comovement of output, employment, and investment across the two sectors. We develop a two sector growth model to explain the observed pattern of comovements, and suggest that intermediate inputs produced by the nondurable goods sector for the durable goods sector play a crucial role.

This article reports the recent progress made by researchers trying to build business cycle models that can reliably reproduce aggregate U.S. time series. The article first describes some features of the U.S. data that the models are meant to reproduce. Then it describes a version of the standard business cycle model, along with the indivisible labor extension of that model, both of which assume that fluctuations in economic activity are caused only by shocks to technology. Finally, it describes a version of recent other extensions which assume that shocks to fiscal variables also contribute to the fluctuations. Adding fiscal shocks to standard business cycle models is shown to significantly improve their ability to mimic some of the data.

This article estimates the benefits of reducing U.S. inflation below its current level when the government simultaneously raises another distortionary tax. Other researchers have suggested that reducing inflation would have fairly large benefits—from 1 to 3 percent of gross domestic product. But that result depends on the unrealistic assumption that the government would replace inflation with a lump-sum tax, one which does not affect people's incentives. If, instead, inflation is replaced with an increase in the labor income tax, then the welfare gains that can be expected from reducing inflation below its current level are much smaller—from one-third to one-half of 1 percent of gross domestic product.

In this paper we study the dynamic behavior of stock returns and volatility in emerging financial markets. In particular, we focus our attention on the following questions:

o Does stock return volatility in emerging markets change over time? If so, are volatility changes predictable?

o How frequent are big surprises in emerging stock markets?

o Is there any relationship between market risk and expected returns?

o Has liberalization affected return volatility in emerging financial markets?

Our findings can be summarized as follows. First, there is strong evidence of predictable time-varying volatility in almost all countries. In general, changes in volatility are highly persistent. Second, a fat-tailed distribution improves the fitting ability of the model. Third, investors are not rewarded for market-wide risk. Finally, we do not find any systematic effect of liberalization on stock market volatility.

We examine the results of four static applied general equilibrium (AGE) modeling teams' analyses of the effects of NAFTA. What they show is that Mexico's economy, because it's the smallest, will see the biggest NAFTA-produced increase in economic welfare: from 2 to 5 percent of GDP. The U.S. welfare increase will be small, around 0.1 percent of GDP; Canada will notice no welfare increase due to NAFTA. We then discuss two examples of dynamic phenomena—labor force adjustment and capital flows—which are likely to influence NAFTA's welfare impact, but that aren't easy to incorporate into static AGE models. Early results indicate that this is an important direction for future study.