COWLES FOUNDATION FOR RESEARCH IN ECONOMICS
AT YALE UNIVERSITY

Box 208281
New Haven, CT 06520-8281

COWLES FOUNDATION DISCUSSION PAPER NO.1730

Default Penalty as Disciplinary and Selection Mechanism in Presence of Multiple Equilibria

Juergen Huber, University of Innsbruck
Martin Shubik, Yale University
Shyam Sunder Yale University

October 2009

Closed exchange and production-and-exchange economies may have multiple equilibria, a fact that is usually ignored in macroeconomic models. Our basic argument is that default and bankruptcy laws are required to prevent strategic default, and these laws can also serve to provide the conditions for uniqueness. In this paper we report experimental evidence on the effectiveness of this approach to resolving multiplicity: society can assign default penalties on fiat money so the economy selects one of the equilibria. Our data show that the choice of default penalty takes the economy to the neighborhood of the chosen equilibrium. The theory and evidence together reinforce the idea that accounting, bankruptcy and possibly other aspects of social mechanisms play an important role in resolving the otherwise mathematically intractable challenges associated with multiplicity of equilibria in closed economies. Additionally we discuss the meaning and experimental implications of default penalties that support an active bankruptcy-modified competitive equilibrium.

JEL Classification: C73, C92, D51, E42, G21, G33

Keywords: Bankruptcy penalty, Financial institutions, Fiat money, Multiple equilibria, Experimental gaming