In contrast to the standard approach in energy economics, this paper assumes that physical capital accumulation is relatively more energy-intensive than consumption. By means of Gaussian hypergeometric functions, we provide a closed-form representation of the optimal solution paths of our variables in levels, whatever the initial conditions (i.e., global dynamics). We find that, in general, the optimal trajectories are nonmonotonic. P.S. Dasgupta and G.M. Heal [Review of Economic Studies (special number), 3–28 (1974)] pointed out this result (local dynamics) for the optimal consumption in a model with identical technology for both physical capital accumulation and consumption. However, our paper introduces five novelties with respect to their study, namely, global dynamics, the importance of the proportion of nonrenewable energy resources to endowment of physical capital [S(0)/K(0)], the role of technical progress, U-shaped behavior of consumption, and nonmonotonicity of resource extraction.

This paper analyzes the effects of technological risk on long-run growth when labor supply is elastic and production gives rise to a pollution externality. We show that the randomness of production, as well as the endogeneity of labor supply, affects the equilibrium solutions for the social planner and for the market economy. We analyze the effects of environmental policy, discuss conditions for an optimal policy, and find that the response of labor supply to changes in the model parameters and to variations in the policy instruments crucially depends on the volatility of output.

We investigate how stochastic asset price dynamics with herding and financial constraints explains the presence of a period of financial distress (PFD) following the peak and preceding the crash of a bubble [Charles P. Kindleberger, Manias, Panics, and Crashes: A History of Financial Crisis, 4th ed. (New York: Wiley, 2000, Appendix B)] as common among most major historical speculative bubbles. Simulations show that the PFD is due to (1) agents' wealth distribution dynamics and (2) positive and sufficiently high transaction costs generating losses for a significant mass of the agents' distribution after the peak of the bubble. The use of transaction costs to get the result is only a modeling tool. Many other mechanisms—able to generate losses for a large mass of the agents' distribution in periods in which financial constraints bind—can produce the same result. The paper also shows how the PFD is affected by a variation of the sensitivity of price to the excess demand and by the switching strategy.

By endowing his agents with simple forecasting models, or representations, M. Woodford (“Learning to Believe in Sunspots,” Econometrica 58, 277–307, 1990) found that finite state Markov sunspot equilibria may be stable under learning. We show that common factor representations generalize to all sunspot equilibria the representations used by Woodford. We find that if finite state Markov sunspots are stable under learning then all sunspots are stable under learning, provided common factor representations are used.

We pursue a semiparametric approach to examining core implications of the Fisher hypothesis, namely cointegration linking nominal interest rates and inflation, and homogeneity of the potential equilibrium relation. The sample is an unbalanced panel and comprises monthly time series from more than 100 economies. The time period of at most 45 years is subdivided into three regimes according to dominating monetary policies. To exploit the cross-sectional dimension for inference on parameter homogeneity, we apply mean group estimation of functional coefficients that allow the conditioning of key model parameters on economic states. The evidence in favor of cointegration is weakened over states of negative real interest rates that are likely to coincide with scenarios of high inflation. The ex post real interest rate is mostly diagnosed as unstable. The Fisher hypothesis is particularly confirmed for states characterized by large positive interest rate adjustments during the inflation-targeting regime.

A canonical flexible-price international real–business cycle model with incomplete financial markets can address the exchange rate–volatility puzzle, the exchange rate–persistence puzzle, and the consumption real–exchange rate anomaly, as well as the quantity anomaly. Crucial for the success of the model is the choice of the elasticity of substitution between home and foreign produced goods. The paper shows that the range of this parameter that allows the model to address these international macroeconomics anomalies is very narrow. Furthermore, the paper highlights an anomalous relationship between real–exchange rate persistence and the elasticity of substitution between home- and foreign-produced goods.