Intertemporal substitution in consumption, labor supply elasticity and sunspot fluctuations in continuous-time models

The aim of this paper is to discuss the roles of the elasticity of intertemporal substitution in consumption and the elasticity of the labor supply on the local determinacy properties of the steady state in a two-sector economy with constant elasticity of substitution technologies and sector-specific externalities. Our main results provide necessary and sufficient conditions for local indeterminacy. First, we show that the consumption good sector needs to be capital intensive at the private level and labor intensive at the social level. Second, we prove that under this capital intensity configuration, the existence of sunspot fluctuations is obtained if and only if the elasticity of intertemporal substitution in consumption is large enough but the elasticity of the labor supply is low enough. In particular, we will show on the one hand that when the labor supply is infinitely elastic, the steady state is always saddle-point stable, and on the other hand that when the elasticity of intertemporal substitution in consumption is infinite, labor does not have any influence on the local stability properties of the equilibrium path.     

Sunspots and Hopf bifurcations in continuous time endogenous growth models

First we treat a three-dimensional continuous time abstract stationary model that includes one predetermined variable and two non-predetermined variables. We construct stationary sunspot equilibria in this model under the following two alternative conditions: (i) a steady state has two stable roots and one unstable root; and (ii) A closed orbit has a two-dimensional manifold on which it is asymptotically stable. Next, we apply these results to the models due to Lucas and Romer that undergo Hopf bifurcations for some parameter values. We construct sunspot equilibria in these models.     

Indeterminacy with small externalities: The role of non-separable preferences

In this paper we consider a Ramsey one-sector model with non-separable homothetic preferences, endogenous labor and productive external effects arising from average levels of capital and labor. We show that indeterminacy cannot arise when there are only capital externalities but that it does occur when there are only labor external effects. We prove that sunspot fluctuations are fully consistent with small market imperfections and realistic calibrations for the elasticity of capital–labor substitution (including the Cobb-Douglas specification) provided the elasticity of intertemporal substitution in consumption and the elasticity of labor supply are large enough.     

Time preference and two-country trade

We present a dynamic two-country model of international trade with endogenous time preference. We show that if the two countries have similar preferences, production technologies and labor endowments, there exists a unique and stable steady state such that both consumption and investment goods are produced in both countries. Unlike the case of constant time preferences, the steady state is independent of the initial international distribution of capital. We prove a dynamic Heckscher–Ohlin theorem such that the labor-abundant country exports the labor-intensive good.     

Multiple equilibria in a cash-in-advance two-sector economy

We consider a two-sector infinite horizon economy with a fractional cash-in-advance constraint on consumption expenditures. This formulation allows us to consider a steady-state velocity of money that is strictly greater than one and, therefore, provides a more plausible framework than the standard formulation in which all the consumption purchases are paid cash. We prove that the steady state is bound to be indeterminate and multiple equilibria occur when the share of the liquidity constraint is low enough and that a capital-intensive investment good or a strongly capital-intensive consumption good improve considerably the scope for indeterminacy. As a consequence, we show that without any restriction on the elasticity of intertemporal substitution in consumption, multiple equilibria might occur if the velocity of money is greater than a critical bound that is compatible with empirical estimates.     

International capital flows,debt overhang and volatility

This paper shows how international capital flows originate boom‐bust and sunspot episodes in a neoclassical growth model of a small, open economy. A limit is imposed on how much the economy can borrow from foreign creditors and it is made endogenous by assuming that the debt‐to‐GDP ratio is procyclical. The steady state is locally indeterminate when the credit multiplier is larger than some threshold level, whereas saddle‐point stability prevails when the credit multiplier is low enough. As a consequence, high levels of the credit multiplier lead to both booms followed by busts and sunspot‐driven volatility near the steady state, while, in contrast, low levels ensure monotonic convergence. Compared with saddle‐path equilibria, boom‐bust and sunspot equilibria are associated with both lower welfare and debt overhang, that is, a crowding‐out effect of credit: when the economy is highly leveraged, it uses savings to cut down foreign debt, at the expense of both human and physical investment. Numerical examples show that indeterminacy arises for debt‐to‐GDP ratios that fall within the range of available estimates. Finally, the effects of shocks to the world interest rate on output and consumption are amplified and persistent in the debt overhang regime.     

Production externalities and local dynamics in discrete-time multi-sector growth models with general production technologies

The present paper examines the dynamic properties of discrete-time, multi-sector growth models in the presence of sector-specific externalities. It extends the literature by allowing for multiple capital good sectors with general social constant returns production technologies. We establish conditions for the steady-state equilibrium to be locally determinate or locally indeterminate, depending crucially on the ratios of the social to private marginal products and the number of capital good sectors. We show that when the ratios of the social to private marginal products are uniform across all sectors, the steady state is always locally determinate in a two-sector model, although local indeterminacy might still arise when the economy features more than two sectors.     

Homoclinic bifurcation and global indeterminacy of equilibrium in a two-sector endogenous growth model

This paper considers an endogenous growth model that belongs to the same family as the Lucas model. In the Lucas model an external effect appears in the physical-goods sector, whereas in our model, it appears in the educational sector. In our model, this external effect yields multiple balanced growth paths. Our model undergoes a homoclinic bifurcation and exhibits global indeterminacy of equilibrium.     

Indeterminacy and Pollution Haven Hypothesis in a Dynamic General Equilibrium Model

This paper develops a two-sector dynamic general equilibrium model of a small open economy in which production activities are accompanied by pollution emissions that have a negative effect on welfare. It is shown that the dynamic equilibrium may display indeterminacy (i.e., continuum of dynamic equilibrium paths converging to a common steady state), depending on (i) the relationship between capital intensity and pollution intensity, (ii) the property of households’ discount rate as a function of total pollution, and (iii) the pollution-consumption relationship in instantaneous utility. In addition, the effect of environmental policy on the economy’s comparative advantage and its relation to indeterminacy are examined.     

Monetary Union and the Interest-Exchange Rate Trade-off

By using a multi-country simulation model this paper analyzes the qualitative effects of joining a monetary union. The transition to EMU (European Monetary Union) is shown to produce interest and exchange rate changes with substantial and countervailing effects on the real economy which can be traced through the model. Observable anticipation effects in the wake of the EMU are substantiated; and some policy recommendations for joining any monetary union are derived. It is also shown that fixing conversion rates at last-day market rates produces a unique outcome and not exchange rate indeterminacy as argued by De Grauwe (1997), Obstfeld (1998), and others.     

Time preference and international trade

We first consider a closed model, where households' time discount depends on externality in consumption. We can prove that there is a unique steady state, which is a saddle point. Then we extend the model to a two‐country world, and derive the condition on the effects of consumption externality under which there is a unique free trade steady state with saddle‐point stability.     

Negishi–Solow efficiency wages, unemployment insurance and dynamic deterministic indeterminacy

This paper introduces efficiency wages designed to provide workers with incentives to make appropriate effort levels, and involuntary unemployment, along the pioneering lines of Negishi (1979) , Solow (1979) and Shapiro and Stiglitz (1984) , in a dynamic model involving heterogeneous agents and financial constraints as in Woodford (1986) and Grandmont et al. (1998) . Effort varies continuously while there is unemployment insurance funded out of taxation of labor incomes. Increasing unemployment insurance is beneficial to employment along the deterministic stationary state, and can even in some cases lead to a Pareto welfare improvement for all agents, through general equilibrium effects, by generating higher individual real labour incomes, hence larger consumptions of employed and unemployed workers, and thus higher production. In contrast, the local (in)determinacy properties of the stationary state are opposite to those obtained in the competitive specification of the model: local determinacy (indeterminacy) occurs for elasticities of capital-efficient labor substitution lower (larger) than a quite small bound. Increasing unemployment insurance is more likely to lead to local indeterminacy and, therefore, to generate dynamic inefficiencies due to the corresponding expectations coordination failures.     

Equilibrium Selection in an Experimental Macroeconomy

In this paper we report the results of an experiment designed to study the behavior of a laboratory macroeconomy with two stable steady states. The economy has the structure of an optimal growth model in which resources are allocated between consumption and investment over a sequence of time periods. The economy is decentralized, with a market for capital in operation. We find that the economy often falls into the Pareto-inferior steady state, which can be viewed as a poverty trap. The initial endowment of capital stock is varied as a treatment variable in the experiment, and the economy is more likely to reach the optimal steady state when its initial endowment is high than when it is low. Organizing the economy with a central planner directing economic activity fails to induce it to reach the optimal steady state.     

Endogenous fertility cycles and childcare services

We construct a two-sector overlapping generation model with endogenous fertility, where one sector produces goods and the other produces childcare services. The elasticity of fertility-related expenditures on services is crucial for determining labor participation and whether fertility converges to a steady state with monotone or oscillation. If capital intensity in the goods sector is greater than the products of elasticity and capital intensity in the service sector, then capital per capita and fertility converge to a steady state monotonically. Conversely, they converge to a steady state with oscillations, otherwise. We find an inverse J-shaped relationship between fertility and elasticity.     

Banking reforms in eastern European countries

This paper investigates the present state of reforms in thebanking sector of the central European countries, with occasionalcomparisons with other eastern European countries. Progressis variable across the countries of the region, but in all countriesbanking reforms generally lag reforms in other areas and muchremains to be done. Regulation generally takes the EuropeanUnion's regulatory framework as a model. Progress on paper ismuch more advanced than implementation and, as a result, allbanking systems in the region are fragile and prey to instability.The paper also looks at basic performance indicators and arrivesat the conclusion that even basic intermediation has remainedrudimentary and quite inefficient. This analysis suggests theurgency of the following measures: (I) the further opening-upof the sector to foreign penetration; (ii) the withdrawal ofthe state from bank ownership; (iii) the speeding-up of implementationof existing regulations; and (iv) the completion of the regulatoryframework, adding specific measures dealing with local problemsthat are not reflected in the 'imported' regulatory map.     

On the stabilizing virtues of imperfect competition

We analyze the stabilizing role of imperfect competition on fluctuations as a result of indeterminacy and endogenous cycles. In this paper, imperfect competition is a source of monopoly profits, because of producer market power. Considering an overlapping generations model with capital accumulation and elastic labor supply, we show that under imperfect competition, the emergence of endogenous fluctuations requires a weaker substitution between production factors than under perfect competition. In this sense, imperfect competition stabilizes fluctuations. However, we find an opposite conclusion concerning the elasticity of labor supply. Indeed, endogenous fluctuations are compatible with a less elastic labor supply under imperfect competition.     

The Effects of Inflation in a Small Open Economy with Durability in Consumption

This paper explores the dynamic effects of inflation in a small open economy when consumption exhibits certain degree of durability. With labor/leisure choice, and money introduced through a cash-in-advance (CIA) constraint on consumption expenditure, it is demonstrated that higher inflation reduces the steady state level of employment, investment, output and consumption. The country runs a current account surplus, despite the fall in output. Consistent with empirical evidence, durable consumption exhibits initial excess volatility. Numerical calibration shows that the steady state real effects of inflation are very significant in this model.     

Maintenance expenditures and indeterminacy under increasing returns to scale

This paper develops a one-sector real business cycle model in which competitive firms allocate resources for the production of goods, investment in new capital and maintenance of existing capital. Firms also choose the utilization rate of existing capital. A higher utilization rate leads to faster capital depreciation, and an increase in maintenance activity has the opposite effect. We show that as the equilibrium ratio of maintenance expenditures to GDP rises, the required degree of increasing returns for local indeterminacy declines over a wide range of parameter combinations. When the model is calibrated to match empirical evidence on the relative size of maintenance and repair activity, we find that local indeterminacy (and belief-driven fluctuations) can occur with a mild and empirically-plausible degree of increasing returns: approximately 1.08.     

外商投资零售企业的竞争优势分析

我国行政编制下的各级地方政府是经济运行中的特殊利益主体。在经济转型过程中,受不同的经济体制运行要求的影响,地方政府间竞争的内涵与方式动态地演变。地方政府间竞争对我国在改革中实现经济较快增长、保持社会稳定发挥了巨大的作用,担当了市场化渐进的中间过渡角色,也     

Sustainability with endogenous discounting

We construct a dynamic competitive model with a stock of human‐made capital and several stocks of natural resources and ask under what conditions consumption will be constant if infinitesimal households with heterogeneous preferences and endowments discount their utility at an endogenous rate that depends on some macroeconomic variables. We show that for consumption to be constant, this function must be the marginal product of capital function. We demonstrate that Hartwick's rule holds in a modified form that takes account of natural growth of resource stocks.