This paper analyzes the dependence of average consumption on the saving rate in a one-sector neoclassical Solow growth model with production shocks and stochastic rates of population growth and depreciation where arbitrary ergodic processes are considered. We show that the long-run behavior of the stochastic capital intensity, and hence average consumption along any sample path, is uniquely determined by a random fixed point that depends continuously on the saving rate. This result enables us to prove the existence of a golden-rule saving rate that maximizes average consumption per capita. We also show that the golden-rule path is dynamically efficient. The results are illustrated numerically for Cobb–Douglas and CES production functions.

This paper studies the evolution of China’s exchange rate policy using real options theory. With intervention costs and ongoing uncertainty, intervention involves the exercise of an option. Increased uncertainty increases the value of this option. This “wait and see” effect leads the Central Bank to widen its intervention band. However, increased volatility also produces larger fluctuations in welfare, which creates a “fear of floating.” This induces the Central Bank to set a tighter band. To study this trade-off, our paper incorporates stochastic volatility into a new Keynesian target zone model and then calibrates it to data from China. We find that increased uncertainty leads to a tighter intervention band, both in the data and in the model. Hence, in China, “fear of floating” appears to dominate the “wait and see” effect.

We estimate a medium-scale dynamic stochastic general equilibrium (DSGE) model for the euro area in an open-economy framework. The model includes structural trends on all variables, allowing us to estimate on gross data. First, we provide a theoretical balanced growth path consistent with permanent productivity shocks, inflation target changes, and permanent shocks to the openness of the economies. We then define the cycle as the gap between this sustainable trajectory and the gross data. Hence, we can properly deal with persistent deviations of the trade balance. Finally, we find persistent and strong effects from the asymmetric increase of euro-area imports during the last 10 years on domestic inflation. From 2000Q1 to 2008Q4, we estimate the contribution of the imbalanced development of international trade on euro-area inflation to an average of −0.7%, and on nominal interest rate, to an average of −1.4%.

This paper presents an overlapping generations model with technology choice and imperfect financial markets, and examines the evolution of the income distribution in economic development. The model shows that improvements in financial infrastructure facilitate economic development both by raising the aggregate capital–labor ratio and by causing a technological shift to more capital-intensive technologies. Although a higher capital–labor ratio under a given technology reduces inequality, a technological shift can lead to a concentration of economic rents among a smaller number of agents. We derive the condition under which an improvement in financial infrastructure actually decreases the average utility of agents.

Most papers studying the impacts of technology adoption on income trajectories assume that firms adopt frontier technologies when available. If these technologies are skill intensive, less-developed economies may fail in successfully implementing them and may become trapped in a low-growth equilibrium. Within a Schumpeterian growth model, we show that differences in adoption barriers and incentives to the accumulation of skills produce differences in the technology level that is optimal to adopt. If the economy is not overly distorted, copying nonfrontier technologies helps compensating for the scarcity of skills and increases the likelihood of copying frontier technologies in the long run. If distortions are significant, it may be optimal to copy less-advanced technologies even in the long run. If adoption is not a skill-intensive activity, then copying frontier technologies is always optimal; all economies achieve a high-growth equilibrium and only income differences persist in the long run.

We identify international output and inflation uncertainty and analyze their impact on individual countries' macroeconomic performance. Output and inflation uncertainty on an international level is measured through the conditional variances of common factors in inflation and output growth, estimated from a bivariate dynamic factor model with GARCH errors. The impact of international and country-specific uncertainty is analyzed by including the conditional variances as regressors. We find increases in uncertainty during the first and second oil crisis, the 1980s and 1990s recessions as well as the recent Great Recession to be confined to the international level. The effect of international uncertainty results to be highly significant and unambiguously negative on countries' output growth and inflation rates whereas the impact of country-specific uncertainty is very mixed.

How much can government-driven mortgage modification programs reduce the mortgage default rate? I compare an economy without a modification option to one with easy modifications, and evaluate the impact of these loan modifications on the foreclosure rate. Through loan modification, mortgage servicers can mitigate their losses and households can improve their financial positions without having to walk away from their homes. When modifying loan contracts is prohibitively costly, the default rate increases 1.5 percentage points in response to a 2007-style unexpected drop in housing prices of 30%. I calibrate the cost of modification after the financial crisis to match the Home Affordable Modification Program (HAMP) modification rate of 0.68%. My quantitative exercises show that current government efforts to promote mortgage modifications reduce the mortgage default rate by 0.63 percentage points.

Following a contractionary monetary policy shock, the aggregate output decreases over time for six to eight quarters, while the real interest rate increases immediately and remains high for three quarters, which can hardly be replicated by models characterized by a standard consumption Euler equation. This paper adopts a segmented markets framework where some households are permanently excluded from financial markets. The aggregate output and the nominal interest rate are modeled as exogenous autoregressive processes, while the real interest rate is determined endogenously. For intermediate levels of market segmentation, the model is able to account for both the persistent decreasing path of the aggregate output and the persistent increase in the real interest rate which follow an unanticipated increase in the nominal interest rate. The sign, the size and the persistence of the responses of the real interest rate and the money growth rate are close to those in the data.

This paper shows that global indeterminacy may characterize the three-dimensional vector field implied by the Lucas [(1988) Journal of Monetary Economics 22, 3–42] endogenous growth model. To achieve this result, we demonstrate the emergence of a family of homoclinic orbits connecting the steady state to itself in backward and forward time, when the stable and unstable manifolds are locally governed by real eigenvalues. In this situation, we prove that if the saddle quantity is negative, and other genericity conditions are fulfilled, a stable limit cycle bifurcates from the homoclinic orbit. Orbits originating in a tubular neighborhood of the homoclinic orbit are then bound to converge to this limit cycle, creating the conditions for the onset of global indeterminacy. Some economic intuitions related to this phenomenon are finally explored.

We build a model of search and matching in which agents trade using coins that are imperfectly recognizable, but have access to a coin inspection technology—known as coin assaying—that reveals the intrinsic content of coins for a fee. We consider two sources of imperfect information: counterfeit coins and clipping. With counterfeits, coin assaying reduces the extent of inefficiencies associated with imperfect recognizability of coins (namely lower traded quantities and lower trading frequencies). Yet coin assaying does not necessarily increase welfare, because it unmasks counterfeits that then trade at a discount, reducing total output. With clipping, we show that agents clip for two reasons: in the hope of passing an inferior coin for a superior one, and to reduce the purchasing power of coins that are too valuable. Although coin assaying could remove the first type of clipping, it had no effect on the second.

A classic result in dynamic public economics states that there is no welfare rationale for pay-as-you-go (PAYG) pensions in a dynamically efficient overlapping-generations economy with exogenous labor supply. Parenthetically, a welfare justification for PAYG pensions exists if the economy is dynamically inefficient. Under the sufficient condition that the old be no less risk-averse than the young, both these results extend to an economy with endogenous labor supply.

This paper examines the effect of the elasticity of technological substitution on the existence of equilibrium indeterminacy in two-sector economies. Following recent empirical evidence, the elasticity of substitution between capital and labor is below unity and we find that this requires a higher degree of productive externalities in order to still be able to produce indeterminate equilibria. However, empirically realistic rates of substitution do not rule out indeterminacy.

This study constructs a variety expansion growth model with public research spending. Public researchers financed by taxes on asset income, consumption, and corporate profits raise the productivity of private research and development. We show that the welfare-maximizing level of public research spending is below the growth-maximizing level. With regard to tax policy, a zero-profit tax maximizes the welfare of households. In addition, the study analyzes the dynamics of the economy, showing that equilibrium is indeterminate when the government's revenue source depends on an asset income tax.

Building on the time-varying-coefficient (TVC) model, we propose a generalization of the concept of cointegration, allowing for the possibility that a set of variables measured with error entails a nonlinear relationship with unknown functional form. Both the dependent and explanatory variables of this relationship may be nonstationary (not necessarily of unit-root type), but there exists a nonlinear combination of all these explanatory variables that completely explains all the variation in the dependent variable. The TVC model allows us to test for the presence of this generalized cointegration in the absence of knowledge of the true nonlinear functional form and the full set of explanatory variables. We present the basic stages of the technique and discuss in detail how the issues of nonstationarity and cointegration affect each stage of the TVC estimation procedure.

This paper develops a dynamic stochastic general equilibrium (DSGE) model with sticky prices and sticky wages, in which agents have imperfect information on the stance and direction of monetary policy. Agents respond by using Kalman filtering to unravel persistent and temporary monetary policy changes in order to form optimal forecasts of future policy actions. Our results show that a New Keynesian model with imperfect information and real rigidities can account for several key effects of an expansionary monetary policy shock: the hump-shaped increase in output, the delayed and gradual rise in inflation, and the fall in the nominal interest rate.

We investigate the business cycle effects of imperfect transmission of technology shocks within a basic real business cycle (RBC) model along two dimensions. First, we assume that agents cannot distinguish a temporary increase in productivity growth from a sustained increase in the underlying growth rate of productivity and instead must conduct signal extraction exercises and update beliefs about the source of aggregated shocks. Second, we propose a technology adjustment cost resulting in the slow diffusion of technological innovations into the production process. Both of these impediments to the transmission of technology result in a large initial wealth effect, increasing investment and hours less, relative to the usual RBC model without these frictions. Furthermore, each of these features is capable of producing a decline in hours on impact of the technology shock matching the negative response in hours found in the data by such works as Gali [American Economic Review 89(1), 249–271 (1999)].

This paper uses a dynamic stochastic general equilibrium model of a two-sector small open economy to analyze how the Maastricht criteria modify a fully credible optimal monetary policy in the Economic and Monetary Union accession countries. We show that if the country is not constrained by the criteria, optimal policy should stabilize fluctuations in PPI inflation, in the aggregate output gap, and in the domestic and international terms of trade. The optimal policy constrained permanently by the Maastricht criteria is characterized by reduced variability of the nominal exchange rate, CPI inflation, and the nominal interest rate and by lower optimal targets for CPI inflation and nominal interest rate. This policy results in higher variability and nonzero means for both PPI inflation and output gap, thus leading to additional, but small, welfare costs compared with the unconstrained policy.

While Perron and Wada (2009) maximum likelihood estimation approach suggests that postwar US real GDP follows a trend stationary process (TSP), our Bayesian approach based on the same model and the same sample suggests that it follows a difference stationary process (DSP). We first show that the results based on the approach should be interpreted with caution, as they are relatively more subject to the ‘pile-up problem’ than those based on the Bayesian approach. We then directly estimate and compare the two competing TSP and DSP models of real GDP within the Bayesian framework. Our empirical results suggest that a DSP model is preferred to a TSP model both in terms of in-sample fits and out-of-sample forecasts.

I examine whether an RBC model can generate a higher volatility of consumption relative to output, a strong negative correlation between output and the trade balance, and a weak countercyclicality of the real interest rate, phenomena that have been observed in the business cycles of emerging economies, including Korea. From an RBC model with recursive utility, I show that it is not the degree of relative risk aversion, but the elasticity of intertemporal substitution (EIS), that governs the movements of the variables of the model in the log linearized environment. The Bayesian estimation results based on Korean data from the period 1987 to 2013 suggest that there are some elements of success in describing the Korean economy based on the simple RBC model both with the EIS larger than one and with an error term for the real interest rate equation. An EIS larger than one improves the performance of the simple RBC model mainly in the direction of raising the volatility of consumption relative to output. Simulation results show that the error term for the real interest rate process mostly reflects the endogenous channel of financial frictions where the domestic real interest rate depends negatively on the expected (transitory) productivity shock.

The aim of this paper is to examine whether the development of waste recycling activities can be a source of economic fluctuations. We assume that the recycling sector has four fundamental characteristics. (i) The production factors are restricted by the production of the last period. (ii) These production factors are waste for which the price determination is noncompetitive. (iii) The sector produces a recycled good, which is a perfect substitute for the primary good. (iv) It reduces the waste stream. We consider the simplest economy, with an infinitely lived agent and a life-cycle hypothesis for the goods. We show that the equilibrium is unique and is always determinate. In spite of the lack of indeterminacy, however, our economy can display cyclical behavior, depending on some usual conditions on parameters. Namely, the steady state may undergo a flip bifurcation or a Hopf bifurcation.