Abstract
Can extrinsic uncertainty ("animal spirits," "market psychology," "sunspots,"...) play a significant role in rational expectations equilibrium models? We establish that extrinsic uncertainty cannot matter in the static Arrow-Debreu economy with complete markets. But we also establish that extrinsic uncertainty can matter in the overlapping-generations economy with complete markets but where market participation is limited to those consumers alive when the markets are open. Equilibrium allocations in which extrinsic uncertainty plays no role are Pareto optimal in the traditional sense. Equilibrium allocations in which extrinsic uncertainty does play a role are Pareto optimal in a (weaker) sense which is appropriate to dynamic analysis.
Keywords
EconomicsPareto principleArrowSunspotMicroeconomicsRational expectationsGeneral equilibrium theoryMathematical economicsEconometricsComputer sciencePhysics
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Publication Info
- Year
- 1983
- Type
- article
- Volume
- 91
- Issue
- 2
- Pages
- 193-227
- Citations
- 989
- Access
- Closed
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Cite This
David Cass,
Karl Shell
(1983).
Do Sunspots Matter?.
Journal of Political Economy
, 91
(2)
, 193-227.
https://doi.org/10.1086/261139
Identifiers
- DOI
- 10.1086/261139