Akos Valentinyi

Growth and Structural Transformation

Structural transformation refers to the reallocation of economic activity across the broad sectors agriculture, manufacturing and services. This review article synthesizes and evaluates recent advances in the research on structural transformation. We begin by presenting the stylized facts of structural transformation across time and space. We then develop a multi-sector extension of the one-sector growth model that encompasses the main existing theories of structural transformation. We argue that this multi-sector model serves as a natural benchmark to study structural transformation and that it is able to account for many salient features of structural transformation. We also argue that this multi-sector model delivers new and sharper insights for understanding economic development, regional income convergence, aggregate productivity trends, hours worked, business cycles, and wage inequality. We conclude by suggesting several directions for future research on structural transformation.

Ruling Out Multiplicity and Indeterminacy: The Role of Heterogeneity

It is well known that economies of scale that are external to the individual decision makers can lead to self-fulfilling prophecies and the multiplicity or even indeterminacy of equilibrium. We argue that the importance of this source of multiplicity and indeterminacy is overstated in representative agent models, as they ignore the potential stabilizing effect of heterogeneity. We illustrate this in a version of Matsuyamas (1991) two-sector model with increasing returns to scale. Two main results are shown. First, sufficient homogeneity with respect to individual productivity leads to the instability and non-uniqueness of a given stationary state and the indeterminacy of the corresponding stationary state equilibrium. Second, sufficient heterogeneity leads to the global saddle-path stability and the uniqueness of a given stationary state and the global uniqueness of equilibrium.

Noisy Contagion Without Mutation

In a local interaction game agents play an identical stage game against their neighbours over time. For nearest neighbour interaction, it is established that, starting from a random initial configuration in which each agent has a positive probability of playing the risk dominant strategy, a sufficiently large population coordinates in the long-run on the risk dominant equilibrium almost surely. Our result improves on Blume (1995), Ellison (2000), and Morris (2000) by showing that the risk dominant equilibrium spreads to the entire population in a two dimensional lattice and without the help of mutation, as long as there is some randomness in the initial configuration.

Contagion and State Dependent Mutations

Early results of evolutionary game theory showed that the risk dominant equilibrium is uniquely selected in the long run under the best-response dynamics with mutation. Bergin and Lipman (1996) qualified this result by showing that for a given population size, the evolutionary process can select any strict Nash equilibrium if the probability of choosing a nonbest response is state-dependent. This paper shows that the unique selection of the risk dominant equilibrium is robust with respect to state dependent mutation in local interaction games. More precisely, for any given mutation structure there exists a minimum population size beyond which the risk dominant equilibrium is uniquely selected. Our result is driven by contagion and cohesion among players, which exist only in local interaction settings and favor the risk dominant strategy. Our result strengthens the equilibrium selection result of evolutionary game theory.

Determinacy Through Intertemporal Capital Adjustment Costs

It is well known that if there are mild sector-specific externalities, then the steady state of the standard two-sector real business cycle model can become indeterminate and endogenous business cycles can arise. We show that this result is not robust to the introduction of standard intertemporal capital adjustment costs, which may accrue when total capital is adjusted or when each sectors capital is adjusted. We find for both forms of adjustments costs that the steady state is determinate for all empirically plausible parameter values. We also find that determinacy occurs for a much larger range of parameter values when adjusting each sectors capital is costly. (Copyright: Elsevier)

Wealth Distribution, Occupational Choice and the Behaviour of the Interest Rate

This paper develops a model of occupational choice and income distribution in which both the wage rate and the interest rate are determined endogenously. We characterize the evolution of the two endogenous variables to the steady state. The model displays multiplicity of equilibria; some equilibrium configuration are analysed which seem to shed light on the evolution of Eastern European economies.