Teresa Lloyd-Braga

Endogenous Business Cycles and Stabilization Policies

We analyze the effects of simple stylized economic policy rules, or stabilization principles, when fluctuations in economic activity are created endogenously by self_fulfilling volatile expectations. We study a simple monetary competitive model with intertemporally optimizing agents and a government. We only depart from neoclassical orthodoxy by assuming that a cycle or a sunspot equilibrium, not necessarily a steady state, could be the descriptive dynamic rational expectations equilibrium. The government may then well out of welfare concerns want to conduct systematic stabilization policy through transfers, expenditure, and taxation even though this has distortionary effects. We show that the policy rules that stabilize output in a way that is best for welfare involve countercyclical elements in government activity.

Indeterminacy in dynamic models: When Diamond meets Ramsey

In this paper, we consider an aggregate overlapping generations model with endogenous labour, consumption in both periods of life, homothetic preferences and productive external effects coming from the average capital and labour. We show that under realistic calibrations of the parameters, in particular a large enough share of first period consumption over the wage income, local indeterminacy of equilibria cannot occur with capital externalities alone but that it can occur when there are only, however small, labour externalities. More precisely, under gross substitutability, the existence of multiple equilibria requires a large enough elasticity of capital-labour substitution and a large enough elasticity of the labour supply. We also show that if labour externalities are slightly stronger and the elasticity of labour supply is larger, local indeterminacy occurs in a Cobb-Douglas economy. Finally, we show that, as a consequence of our restriction on first period consumption, a locally indeterminate steady state is generically characterized by an under-accumulation of capital. It follows therefore that while agents live over a finite number of periods, the conditions for the existence of locally indeterminate equilibria are very similar to those obtained within infinite horizon models and that from this point of view, Diamond meets Ramsey.

Endogenous Fluctuations In an Open Economy with Increasing Returns to Scale

In this paper we study the effects of opening an economy, with increasing returns in the production of non traded goods, on the existence of multiple Pareto-ranked stationary equilibria, local indeterminacy and bifurcations. We consider a standard Overlapping Generation Model of a small open economy, with a fixed exchange rate, where labour is the only input and money the only asset. We find that when there are increasing returns, the open economy may display persistent equilibrium endogenous fluctuations (deterministic and stochastic) in the balance of trade and main macroeconomic aggregates.

National labor markets, international factor mobility and macroeconomic instability

We analyze how global economic integration of factor markets affects the stability of the macroeconomy, with respect to expectations-driven fluctuations, when countries differ in their labor market institutions. It is shown that, due to the occurrence of equilibrium indeterminacy, liberalization of capital movements is likely to be accompanied by persistent fluctuations at the world level, while allowing also for labor movements may bring macroeconomic stability. Whether this also implies higher welfare in the long run depends on differentials in average firm size across countries. If the average firm size in a country operating under perfect competition and full employment is small relative to a country with rigid wages and unemployment, then free migration reduces unemployment, narrows wage differentials and expands world output.

Can Consumption Taxes Stabilize the Economy in the Presence of Consumption Externalities

We discuss the stabilization role of consumption taxes under a balanced-budget rule in the presence of consumption externalities of the “keeping up with the Joneses” type. We consider a finance constrained economy and depart from a situation where sufficiently strong externalities make the steady state indeterminate, if government intervention is absent. Sufficiently procyclical consumption tax rates are able to ensure local saddle path stability. However, this procyclicality leads to the appearance of another steady state with lower levels of output which is a source or indeterminate. Therefore, government intervention with stabilization purposes may not be successful.

The destabilizing effects of the social norm to work under a social security system

We study employment dynamics in an OLG model with unemployment benefits financed by taxing wages, and with a defined contribution plan. The novelty with respect to recent studies of the effects of social security in this context is that we introduce a social norm to work, shaping the worker’s participation decision, and hence affecting the reservation wage. We find that a strong social norm to work destabilizes conventional wisdom by reversing the negative effects of social security on employment, and destabilizes the economy by facilitating the emergence of endogenous fluctuations.