This paper considers an optimal endogenous growth model where the production function is assumed to exhibit increasing returns to scale and two types of resource (renewable and nonrenewable) are imperfect substitutes. Natural resources, labor, and physical capital are used in the final goods sector and in the accumulation of knowledge. Based on results in the calculus of variations, a direct proof of the existence of an optimal solution is provided. Analytical solutions for the planner case, balanced growth paths, and steady states are found for a specific CRRA utility and Cobb–Douglas production function. It is possible to have long-run growth where both energy resources are used simultaneously along the equilibrium path. As the law of motion of the technological change is not concave, reflecting the increasing returns to scale, so that the Arrow–Mangasarian sufficiency conditions do not apply, we provide a sufficient condition directly. Transitional dynamics to the steady state from the theoretical model are used to derive three convergence equations of output intensity growth rate, exhaustible resource growth rate, and renewable resource growth rate, which are tested based on OECD data on production and energy consumption.

This study examines the driving forces behind the strong decline in German unemployment from 2005 onwards and the exceptionally small increase during the Great Recession. Structural vector autoregressions (VARs) with sign restrictions show that wage moderation in the aftermath of labor market reforms was the dominant factor of the unemployment decline, and that improved matching and shrinking labor supply also contributed to it. The adjustment to business cycle shocks (Great Recession), on the other hand, is to a large extent borne by the intensive margin, which can be explained by institutional aspects of the German labor market.

A central policy issue in the battle against HIV in sub-Saharan Africa (SSA) is whether and when high-prevalence countries might become autonomous in designing and implementing their own intervention policies against the disease. The aim of this research is twofold. First, it develops a framework for explaining economic development in a general equilibrium growth model with endogenous fertility and endogenous mortality forced by the threat of a persistent, deadly infectious disease, such as HIV/AIDS in SSA. Second, it aims to shed light on the interplay between foreign aid and endogenous domestic public policies in SSA countries severely afflicted by HIV. Consequently, it investigates the demographic and macroeconomic implications of an intervention against HIV/AIDS whose total amount is the sum of an exogenous component representing foreign aid and an endogenous public expenditure. On the assumption that these policies allow the same degree of HIV control, we show the emergence of quite different responses in terms of key demo-economic variables. These effects mainly pass through the fertility response to the evolving epidemic conditions.

Linear models with infinite horizon generally admit infinitely many rational expectations solutions. Consequently, some additional selection devices are needed to narrow the set of relevant solutions. The viewpoint of this paper is that a solution will be more likely to arise if it is locally determinate (i.e., locally isolated), locally immune to sunspots, and locally stable under learning. These three criteria are applied to solutions of linear univariate models along which the level of the state variable evolves through time. In such models the equilibrium behavior of the level of the state variable is described by a linear recursive equation characterized by the set of its coefficients. The main innovation of this paper is to define new perfect-foresight dynamics whose fixed points are these sets of coefficients, thus allowing us to study the property of determinacy of these sets, or, equivalently, of the associated solutions. It is shown that only one solution is locally determinate in the new dynamics. It is also locally immune to sunspots and locally stable under myopic learning. This solution corresponds to the saddle path in the saddle-point case.

In this paper we empirically examine the sources of the volatility of the foreign exchange risk premia. Using a nonlinear structural Vector Autoregression (VAR) model based on no-arbitrage condition to identify various macroeconomic shocks and the foreign exchange risk premia, we find that more than 80% of the volatilities of the currency risk premia can be accounted for by the standard macroeconomic shocks that drive output and inflation. By explicitly modelling the currency risk premia in the VAR system, we also offer a potential reconciliation for the seemingly contradicting observations from the previous VAR analysis of the exchange rate “overshooting” behavior under exogenous monetary innovations.

This note builds on recent work by Serletis and Shahmoradi [Macroeconomic Dynamics 9 (2005), 542–559] and estimates the AIM model at different degrees of approximation, using the same optimization procedures as in Gallant and Golub [Journal of Econometrics. 26 (1984), 295–321]. We estimate the models subject to regularity and provide a comparison between the different versions. We argue that the AIM(3) model estimated subject to global curvature currently provides the best specification for research in semiparametric modeling of consumer demand systems.

This paper explores the introduction of collective risk-reallocation elements into defined-contribution pension contracts. We consider status-contingent, age-contingent, and asset-contingent arrangements to reallocate risk among participants. Eliminating asset market risk for the retired raises their welfare, whereas it lowers the welfare of the workers, despite the fact that they benefit later from the same arrangement. Overall welfare falls. The welfare effects are largest when personal and pension portfolios are optimally chosen. Allowing for intragenerational heterogeneity, the highest-skilled retirees benefit most, whereas the highest-skilled workers lose most. Our main results are qualitatively robust to a number of model variations and extensions.

We document the strong evidence of time variation in the volatility of Euro Area business cycles since 1970. Then we provide the quantitative sources of these changes using a medium-scale DSGE model allowing time variation in structural disturbance variances. We show that (1) the size of different types of shock oscillates, in a synchronized manner, between two regimes over time, with the high-volatility regime prevailing predominantly in the 1970s, sporadically in the 1980s and 1990s, and during the Great Recession; (2) their relative importance remains, however, unchanged across regimes, where neutral technology shocks and marginal efficiency of investment shocks are the dominant sources of business cycle fluctuations; and 3) these investment shocks, which affect the transformation of savings into productive capital, can be interpreted as an indicator of credit conditions.

Fiscal discipline is commonly evaluated on the basis of the debt–gross domestic product ratio, which exhibits a stock variable measured relative to a flow variable. This way of monitoring debt solvency is arguably not consistent with transversality conditions obtained from optimizing macroeconomic frameworks. In this paper, we consider a wealth-based sustainability index of government debt policy derived from a baseline endogenous growth model. We calculate the index from 1999 onward for countries in which the after-growth real interest rate is positive, consistently with the theoretical setup. Results are radically different from common wisdom. We show that the fiscal position is sustainable for both Germany and Italy, and strongly unsustainable for both Japan and France. Policy implications of our findings are discussed.

This paper estimates the dynamics of the personal-bankruptcy rate over the business cycle by exploiting large cross-state variation. We find that bankruptcy rates are significantly above trend during a recession and rise as a recession persists. After a recession ends, there is a hangover in which bankruptcy rates begin to fall but remain above trend for several more quarters. Recovery periods see a strong bounce-back effect, with bankruptcy rates significantly below trend for several quarters. Despite the significant increases in bankruptcies during recessions, the largest contributor to rising bankruptcies during these periods has tended to be the longstanding upward trend.

This note uses a nonlinear structural vector autoregression model to empirically investigate the effectiveness of official foreign exchange (FX) interventions in an economy when interest rates are constrained to the zero level, based on Japanese data in the 1990s. The model allows us to estimate the effects of FX interventions operating through different channels. We find that FX interventions are still capable of influencing the foreign exchange rate in a zero-interest-rate environment, even though their effects are greatly reduced by the zero lower bound on interest rates. Our results suggest that although it might be feasible to use the exchange rate as an alternative monetary policy instrument at zero interest rates as proposed by McCallum (Inflation Targeting and the Liquidity Trap, NBER working paper 8225, 2000), the exchange rate–based Taylor rule may not be very effective in achieving the ultimate policy goals.

This paper investigates the intergenerational sharing of shocks on the permanent income of new entry cohorts when prior-to-entry markets are missing. When Lucas trees are traded among generations, procyclical cohort-specific shocks are shared partially via the movement of asset prices; cohorts with lower endowments may benefit more from asset pricing dynamics than cohorts with higher endowments. Given a reasonable set of parameters concerning the Japanese labor market, the evaluated welfare loss ranges from 1% to 3% in terms of the certainty equivalence consumption level. The first-best outcome may be achieved by either a combination of subsidies and taxes or the introduction of prior-to-entry markets.

This note studies the implications of the price reset hazard function for the monetary transmission mechanism of sticky price models. I first document some general analytical results that highlight the central role of the price (accumulative) distribution in linking the hazard function and the impulse response function. I find that nominal rigidity underlying increasing hazard functions is more successful than real rigidity in replicating realistic macro persistence. In addition, numerical simulations show that the interaction between the increasing hazard function and the real rigidity provides a powerful propagation mechanism for monetary shocks.

This paper documents three facts. First, the volatility of consumption growth relative to income growth rose from 1947 to 1960 and then fell dramatically by 50% from the 1960s to the 1990s. Second, the correlation between consumption growth and personal income growth fell by about 50% over the same time period. Finally, the absolute deviation of consumption growth from its mean exhibits one break in U.S. data, and the mean of the absolute deviations has fallen by about 30%. A standard dynamic stochastic general equilibrium model is unable to explain these facts. I examine ability of two hypotheses to account for these facts: a fall in credit constraints and changing beliefs about the permanence of income shocks. I find evidence for both explanations. The beliefs explanation is more consistent with the data.

We study the general equilibrium properties of two growth models with overlapping generations, habit formation, and endogenous fertility. In the neoclassical model, habits modify the economy's growth rate and generate transitional dynamics in fertility; stationary income per capita is associated with either increasing or decreasing population and output, depending on the strength of habits. In the AK specification, growing population and increasing consumption per capita require that the habit coefficient lie within definite boundaries; outside the critical interval, positive growth is associated with either declining consumption due to overcrowding, or extinction paths with declining population. In both frameworks, habits reduce fertility: the trade-off between second-period consumption and spending for bequests prompts agents to decrease fertility in order to make parental altruism less costly. This mechanism suggests that status-dependent preferences may explain part of the decline in fertility rates observed in most developed economies.

In this paper, we investigate the ability of a modified real business cycle (RBC) model to reproduce asymmetries observed for macroeconomic variables over the business cycle. To replicate the empirical skewness of major U.S. macroeconomic variables, we introduce a capacity constraint into an otherwise prototypical RBC model. This constraint emerges because of the assumption of kinked marginal costs of utilization, where the kink is located at a utilization rate of 100%. We find that a model with a suitably calibrated cost function reproduces the empirical coefficients of skewness remarkably well.

We develop a growth model where knowledge is embodied in individuals and diffused across sectors through labor mobility. The existence of labor mobility costs constrains mobility and thus generates labor misallocation. Different levels of labor misallocation imply different levels of exploitation of available knowledge and therefore different total factor productivity across countries. We derive a positive relationship between growth and labor mobility, which is consistent with the empirical evidence, by assuming aggregate constant returns to capital. We also analyze the short- and long-run effects of labor mobility costs in the case of decreasing returns to capital. It turns out that changes in mobility costs have larger economic effects when different types of workers have small rather than large complementarities. Finally, we show that different labor income taxes or labor market tightness imply different rates of labor mobility and therefore can explain differences in Gross Domestic Product across countries.

This paper analyzes the existence of Hopf bifurcation and establishes the conditions under which the equilibrium path converges toward periodic solutions in a one-sector optimal growth model with delay. We establish the limits and the possibilities of nonlinear dynamics (i.e., cycles) vis-à-vis delays. In particular, we formulate a new method to further comprehend the root distribution of the characteristic equation of a standard optimal growth model with delayed investment structure. We show that nonmonotonic dynamics (limit cycles, persistent oscillations) occurs when the delayed investment causes permanent adjustment failures among the economic variables in the economy.

The existing literature dealing with mutual interactions between the extent of oil dependence and the possibility of belief-driven fluctuations unanimously ignores international loans. This simplified assumption disregards the fact that the relative magnitude of the financial account and the trade account exhibits an increasing trend. Faced with this deficiency in the literature, this paper develops a real business cycle model featuring oil dependence in domestic production and international loans, and examines whether both the presence of international borrowings and the dependence on imported energy will govern the emergence of belief-driven fluctuations.

This paper analyzes the behavior of a central bank under strong (“Knightian”) uncertainty when the short-run trade-off between output and inflation is represented by the sticky information Phillips curve proposed by Mankiw and Reis [Quarterly Journal of Economics 117(4), 1295–1328 (2002)]. By solving the robust control problem analytically, we show why model uncertainty does not affect the optimal monetary policy response to demand and productivity shocks, whereas it causes a stronger reaction of the monetary policy instrument to a cost-push (i.e., markup) shock. Differently from what occurs in sticky price models, the antiattenuation effect can result in a degree of price level stabilization that is greater or less than that experienced in the rational expectation model, depending on the central bank's degree of conservatism. These results dramatically affect the rationale for delegating monetary policy to a central banker more conservative than the society.