We study a generic optimal control problem with a stock that accumulates with constant delay. We show that the optimal system dynamics reduces to a system of ordinary differential equations, implying monotonic optimal paths, if the objective function is additively separable in the stock and the control. This is, however, not true for general objective functions, which may exhibit nonmonotonic and oscillatory optimal paths. The reason is that the impact of the stock on the objective depends on the current level of the control, whereas the control influences the dynamics of the stock with a delay.

This paper analyzes the aggregate growth and distributional effects of tax policy using an endogenous growth model with heterogeneous agents having “catching up with the Joneses” (CUJ) types of preferences. We characterize the aggregate equilibrium of this economy, as well as its distributional properties, and show that the consumption externality present with CUJ preferences produces greater income inequality than is obtained with conventional time-separable preferences. The consumption externality substantially alters the effects of tax policy, mostly quantitatively, but in some cases qualitatively as well. Extensive numerical simulations are conducted and used to compare the consequences of different modes of taxation, highlighting the tradeoffs involved.

In the aftermath of the global financial crisis, competing measures of the trend in macroeconomic variables such as U.S. real GDP have featured prominently in policy debates. A key question is whether large shocks to macroeconomic variables will have permanent effects—i.e., in econometric terms, do the data contain stochastic trends? Unobserved-components models provide a convenient way to estimate stochastic trends for time series data, with their existence typically motivated by stationarity tests that allow at most a deterministic trend under the null hypothesis. However, given the small sample sizes available for most macroeconomic variables, standard Lagrange multiplier tests of stationarity will perform poorly when the data are highly persistent. To address this problem, we propose the use of a likelihood ratio test of stationarity based directly on the unobserved-components models used in estimation of stochastic trends. We demonstrate that a bootstrap version of this test has far better small-sample properties for empirically relevant data-generating processes than bootstrap versions of the standard Lagrange multiplier tests. An application to U.S. real GDP produces stronger support for the presence of large permanent shocks using the likelihood ratio test than using the standard tests.

Unlike most existing studies on the endogenous institutions, literature on theoretical growth has traditionally considered institutions as exogenous. In this paper, a learn-by-doing-based growth model is adopted and integrated with endogenous institutions to study how economic agents’ incentives engage in institutional improvements or exploit institutional imperfections. From maximization of identical agent utility, the economic growth model includes capital, labor, technology, and institutions. The study is to analyze the effect of institutions on the stability of equilibrium, balanced economic growth path, and convergence rate in the process of economic growth. It is concluded that, firstly, improving institutions is a decisive factor for China’s high economic growth rate for the past years; secondly, improving institutions can increase the capital stock per unit of effective labor in steady state; thirdly, imperfect institutions can explain income difference among countries; and finally, technology plays a key role only under the conditions adapting to institutions.

We develop a dynamic general equilibrium growth model, where households purchase final goods on cash or credit and have different capital and money endowments, to investigate whether inflation affects trends in income and consumption inequality. We show that, under a strong substitutability between cash and credit goods, inflation has a negative relationship with income inequality, but a U-shaped relationship with consumption inequality. The divergence between income and consumption inequality explains several recent empirical observations. This result has important policy implications, as consumption inequality better reflects the welfare distribution whereas income inequality fails to capture consumption disparities resulting from different consumption and asset distributions across households. In the growth model with heterogeneous households, there is a mixed relationship between growth and income inequality, confirming the existence of the Kuznets curve. The inflation-driven asset reallocation might also produce a Mundell–Tobin effect, enhancing growth.

In this paper, the location patterns of Multinational Enterprises are modeled by an evolutionary two-country model in which producing in a developed economy offers strong cost-reducing externalities of within-country spillovers and opting for a developing economy entails cheap labor but also extra operational costs due to the undersupply of public goods. The offshoring process, that is, manufacturing activity outsourced in the developing economy, increases the bargaining power of its workers and, with it, its labor cost. The investigation underlines that an increasing labor-productivity remuneration in the developing economy may spark a reshoring process that depends on the agglomeration and endowment drivers characterizing an industry. The reshoring process can be narrowed by a flexible labor remuneration scheme, with wages indexed to the domestic concentration of manufacturing activity. The presence of sub-optimal location patterns points out the existence of a trade-off between stability and efficiency, which underlines that policy measures designed to make a country a more efficient location are neither sufficient nor necessary for preventing offshoring or ensuring reshoring.

This paper investigates the effects of R&D subsidies on aggregate product variety and endogenous productivity growth without scale effects. In a two-country model with imperfect knowledge diffusion, the larger country has a greater share of firms with higher productivity levels. The concentration of relatively productive firms increases knowledge flows between firms, causing an increase in firm-level employment in innovation. Accordingly, the aggregate growth rate is higher when counties are asymmetric than when they are similar in size. The larger scale of firm-level innovation activity reduces market entry, however, and aggregate product variety falls. In this framework, national R&D subsidies have positive effects on the industry share, relative productivity, and wage rate of the implementing country. If the smaller country introduces an R&D subsidy, aggregate product variety rises and productivity growth falls. If the larger country introduces an R&D subsidy, productivity growth rises, but aggregate product variety may rise or fall.

Is there an economic justification for why technical change is by assumption labor-augmenting in dynamic macroeconomics? The literature on the endogenous choice of capital- and labor-augmenting technical change finds that technical change is purely labor-augmenting in steady state. The present paper shows that this finding is mainly an artifact of the underlying mathematical models. To make this point, Uzawa's steady-state growth theorem is generalized to a neoclassical economy that, besides consumption and capital accumulation, uses current output to create technical progress or to manufacture intermediates. The generalized steady-state growth theorem is shown to encompass four models of endogenous capital- and labor-augmenting technical change and the typical model of the induced innovations literature of the 1960s.

Discrete-time and continuous-time models with time to build do not possess the same dimension. In this paper we address the dimensionality issue by revising the way time to build is traditionally measured when transforming the economic dynamics from discrete to continuous time. We propose our new procedure as an alternative approach which allows for a unifying theory of the two classes of economic growth models. Interestingly enough, discrete-time models admit a change in stability for a value of the time-to-build parameter where their continuous counterpart admits an Hopf bifurcation.

Using a macroeconomic model with asset prices, we analyze how optimal monetary policy and macroeconomic dynamics and performance are affected by a central bank's desire to be robust against model misspecifications. We show that a higher central bank preference for robustness implies a more aggressive reaction of the nominal interest rate to the expected future inflation rate and inflation shocks. The dynamic stability of the equilibrium is not modified for a sufficiently high preference for robustness. However, the speed of dynamic convergence is lower under robust control compared to a benchmark case without it and implies supplementary economic costs. Finally, an increase in the preference for robustness comes at the cost of higher macroeconomic and financial volatility in the presence of inflation shocks. It has no effect on the reaction of inflation, output gap, and asset price gap to shocks affecting goods and financial markets.

This paper builds a macroeconomic model of equilibrium unemployment in which firms persistently face difficulties in selling their production, and this affects their decisions to create jobs. We show that the competitive search equilibrium is not efficient and that inflation is detrimental to unemployment.

This paper analyzes the relationship between the expectational stability of rational expectations solutions and the possible convergence of adaptive learning processes. Both concepts are used as selection criteria in the case of multiple rational expectations solutions. Results obtained using recursive least squares lead to the conjecture that there exists a general one-to-one correspondence between these two selection criteria. On the basis of a simple linear model and a stochastic gradient algorithm as an alternative learning procedure, it is demonstrated that such a conjecture would be incorrect: There are cases in which stochastic gradient learning converges to rational expectations solutions that are not expectationally stable.

This paper develops an overlapping-generations model to study the growth-maximizing level of public debt under conditions of demograhic change. It is shown that the optimal debt level depends on a positive marginal productivity of public capital. In general, it also depends on the demographic parameters, but not if the government is not allowed to borrow to cover revenue shortfalls for current age-related spending. In that context, balanced budget rules are not an approriate form of fiscal rule. The implication is that a government facing demograhic change or demands for more welfare spending will have to adjust its fiscal plans to accommodate those changes, most likely downward, if growth is to be preserved. An advantage of this model is that it allows us to determine in advance the way in which fiscal policies need to adjust as demographic parameters change.

This paper studies the nature of long-run behavior in a two-sector model of optimal growth. Under some restrictions on the parameters of the model, we provide an explicit solution of the optimal policy function generated by the optimal growth model. Fixing the discount factor, we indicate how long-run optimal dynamics changes as a key technological parameter (labor output ratio) changes. For a particular configuration of parameter values, we also provide an explicit solution of the unique absolutely continuous invariant ergodic distribution generated by the optimal policy function.

This study detects a structural break in international consumer price index (CPI) inflation comovement. We estimate the dynamic common factor models with unknown breakpoints of cross-country inflation rates and global price index of all commodities. We identify two global factors from the models: a commodity global factor and a noncommodity global factor. The former is a common factor between national inflation rates and commodity price index growth; the latter is a common factor among national inflation rates. The estimation of 29 countries’ quarterly CPI inflation data from 2001:Q1 to 2018:Q2 shows a one-time break in cross-country inflation dynamics in 2008:Q4. Thereafter, the importance of global factors in explaining the national inflation rates is remarkably increased. Furthermore, the increased global inflation synchronization is mainly driven by the larger role of the noncommodity global factor rather than that of the commodity global factor.

In this paper, we study the stationary and non-stationary equilibria of a deterministic, pure exchange, two-period overlapping generations model with habit persistence. We show that preferences with multiplicative habits can lead to quite different equilibrium outcomes compared to subtractive ones. The two most commonly adopted habit specifications can differ in terms of homotheticity, gross substitutability, and uniqueness of equilibria. We illustrate these differences in terms of steady-state equilibria, as well as local dynamics.

We formulate a central bank's problem of selecting an optimal long-run inflation rate as the choice of a distorting tax by a planner who wishes to maximize discounted stationary utility for a heterogeneous population of infinitely lived households in an economy with constant aggregate income and public information. Households are segmented into agents who store value in currency alone and agents who have access to both currency and loans. We show that the optimum inflation rate is positive, because inflation reduces the value of the outside option for credit agents and raises their debt limits.

This paper builds a small-open-economy nonscale-growth model with negative population growth and investigates the relationship between trade patterns and per capita consumption growth. Under free trade, if the population growth rate is negative and its absolute value is small, the home country becomes an agricultural country. Then the long-run growth rate of per capita consumption is positive and depends on the world population growth rate. On the other hand, if the population growth rate is negative and its absolute value is large, the home country becomes a manufacturing country. Then the long-run growth rate of per capita consumption is positive and depends on both the home country and the world population growth rates. Moreover, the home country is better off under free trade than under autarky in terms of per capita consumption growth irrespective of whether the population growth is positive or negative.

This paper examines the financial stress interconnectedness among Greece, Ireland, Italy, Portugal, and Spain (GIIPS) economies and Germany. Based on market-level financial stress indices, we examine the stress transmission process as well as the causal network relationships in banking sector, bond, money, and stock markets. The period under investigation, 2001–2013, allows to test the effects of the 2007–2009 financial crisis as well as the subsequent European sovereign crisis. Using two alternative techniques for connectedness analysis, our evidence suggests that the peripheral economies of Italy and Spain play a highly significant role in the stress transmission in all markets, especially in the cases of banks and equity markets. Moreover, we visualize our results using network analysis. Contrary to common wisdom, Portugal, Ireland, and mainly Greece do not seem to have an important role in amplifying stress levels.

This paper presents a Ramsey-like dynamic small open economy with endogenous labor migration. In the model, the domestic economy is free to borrow or lend as much as it wants at the given world interest rate, and individuals are supposed to be free to move from a country to another in response to the emergence of a wage differential between countries. Our analysis can be ideally split in two parts. Initially, we propose a baseline model in which only natives are allowed to save and invest in capital assets and traded bonds, whereas immigrants are credit constrained. Next, we provide an extension in which all individuals, including immigrants, have full access to international financial markets. We find that the steady state is always local indeterminate, and that the adjustment dynamics of the competitive equilibrium is dependent upon the initial level of the immigration ratio.