This issue collects 11 articles at the frontier of the field of Dynamic Macroeconomic Theory.

A majority of the articles discuss theoretical issues related to monetary policy. Many rich economies have now enjoyed a long period of stable monetary conditions, but many researchers remain puzzled as to what are the main mechanisms driving monetary stability. The field is of great importance to policymakers, and this issue's dynamic approaches will advance the debate. The other articles touch on other, equally inherently dynamic issues of macroeconomics, relating to growth, business cycles, and the role of credit. In light of the hard constraints we imposed on the length of the contributed articles, we will let the articles speak for themselves, and hope that the reader will enjoy this research sample as much as we do.

In this paper, we compare the empirical properties of closed- and open-economy DSGE models estimated on Euro area data. The comparison is made along several dimensions; we examine the models in terms of their marginal likelihoods, forecasting performance, variance decompositions, and their transmission mechanisms of monetary policy.

We consider a linear growth model with idiosyncratic productivity shocks in which producers cannot commit to repay their loans. Borrowing constraints are determined endogenously by the borrowers' incentives to repay, assuming that defaulters lose a share of output and are excluded from future trade in the credit market. We characterize necessary and sufficient conditions for the enforceability of a first-best equilibrium growth path. Weak property rights, impatient producers, and small productivity differentials can make the efficient growth path nonenforceable and lead to an inefficient equilibrium with binding borrowing constraints. For some economies, multiple balanced growth paths coexist.

The fiscal theory of the price level says that the price level can be made determinate if the government uses fiscal policies such that government liabilities explode unless the price in the first period is at the “right” level. The policy implications are disturbing, as they call for rather adventurous fiscal policies. We show that these disturbing policy implications are specific to the “Ricardian” models that have been used to develop the theory. By moving to non-Ricardian models, we see that price determinacy is consistent with reasonable fiscal policies.

This paper presents a two-country dynamic general equilibrium model with imperfect competition and nominal price rigidities in which productivity shocks coexist with markup shocks. After analyzing the features of the optimal cooperative solution, we show that this allocation can be implemented in a strategic context through inflation-targeting regimes. Under these regimes, each monetary authority minimizes a quadratic loss function that targets only domestic targets, namely, GDP inflation and the output gap.

We study identification in a class of linear rational expectations models. For any given exactly identified model, we provide an algorithm that generates a class of equivalent models that have the same reduced form. We use our algorithm to show that a model proposed by Jess Benhabib and Roger Farmer is observationally equivalent to the standard new-Keynesian model when observed over a single policy regime. However, the two models have different implications for the design of an optimal policy rule.

We incorporate imperfectly insured unemployment in the finance constrained economy proposed by Woodford (1986), by introducing unions and unemployment benefits financed by labor taxation. We show that this simple extension of the Woodford model changes drastically its stability conditions and local dynamics around the steady state. In fact, in contrast to related models in the literature, we find that, under constant returns to scale in production: (i) indeterminacy always prevails in the case of a unitary elasticity of substitution between capital and labor and (ii) flip and Hopf bifurcations occur for empirically credible elasticities of substitution between capital and labor, so that a rich set of dynamics may emerge at “realistic” parameters' values.

Recent literature on the design of optimal monetary policy has shown that deviations from price stability are small whenever prices are sticky. This paper reconsiders this issue by introducing capital accumulation in the model. Optimal monetary policy in this setup implies small deviations from price stability. The monetary authority optimally uses inflation as an explicit tax on monopolistic profits to reduce the price markup across states. Variable markup is achieved in this setup because the share of investment demand over output varies across states and in response to TFP shocks.

This paper examines the question to what extent premia for macroeconomic risks in banking are sufficient to avoid banking crises. We investigate a competitive banking system embedded in an overlapping-generations model subject to repeated macroeconomic shocks. We show that even if banks fully incorporate macroeconomic risks into their pricing of loans, a banking system may enter bankruptcy with probability one. A major cause for this default is that risk premia of a competitive banking system may become too small if the capital base is low.

This paper computes welfare-maximizing monetary and tax policy feedback rules in a calibrated dynamic general equilibrium model with sticky prices. The government makes exogenous final good purchases, levies a proportional income tax, and issues nominal one-period bonds. A quadratic approximation method is used to solve the model and to compute household welfare. Optimized policy has a strong anti-inflation stance and implies persistent fluctuations of the tax rate and of public debt. Very simple optimized policy rules, under which the interest rate just responds to inflation and the tax rate just responds to public debt, yield a welfare level very close to that generated by richer rules.

We study the effects of model uncertainty in a simple New Keynesian model using robust control techniques. Due to the simple model structure, we are able to find closed-form solutions for the robust control problem, analyzing both instrument rules and targeting rules under different timing assumptions. In all cases but one, an increased preference for robustness makes monetary policy respond more aggressively to cost shocks but leaves the response to demand shocks unchanged. As a consequence, inflation is less volatile and output is more volatile than under the nonrobust policy. Under one particular timing assumption, however, increasing the preference for robustness has no effect on the optimal targeting rule (nor on the economy).

This paper explores the macroeconomic consequences of preferences displaying a subsistence point. It departs from the existing related literature by assuming that subsistence points are specific to each variety of goods rather than to the composite consumption good. We show that this simple feature makes the price elasticity of demand for individual goods procyclical. As a result, markups behave countercyclically in equilibrium. This implication is in line with the available empirical evidence.