Eductive Stability in Real Business Cycle Models

Bruce McGough presented joint work with George Evans and Roger Guesnerie on eductive stability in a standard RBC model. Eductive stability, a stricter form of stability under learning,  refers to a type of equilibrium in which hyper-rational agents endowed with some Common Knowledge  are able to coordinate on an equilibrium. The abstract is below.

Abstract: Within the standard RBC model, we examine issues of expectational coordination on the unique rational expectations equilibrium. Our study first provides a comprehensive assessment of the sensitivity of agents’ plans and decisions to their short-run and long-run expectations. We show this sensitivity is much too great to trigger eductive coordination in a world of hyper-rational agents, who are endowed with Common Knowledge and contemplate the possibility of small deviations from equilibrium: eductive stability never obtains. This impossibility theorem has a counterpart when adaptive learning is incorporated and real-time paths are required to satisfy a collective initial view of the future.

The slides from the presentation are here.