Risk matters: Breaking certainty equivalence in linear approximations

B-Tier
Journal: Journal of Economic Dynamics and Control
Year: 2021
Volume: 133
Issue: C

Score contribution per author:

0.670 = (α=2.01 / 3 authors) × 1.0x B-tier

α: calibrated so average coauthorship-adjusted count equals average raw count

Abstract

In this paper we use the property that certainty equivalence, as implied by a first-order approximation to the solution of stochastic discrete-time models, breaks in its equivalent continuous-time version. We derive a risk-sensitive first-order perturbation solution for a general class of rational expectations models. We show that risk matters economically in a real business cycle (RBC) model with habit formation and capital adjustment costs, and that neglecting risk leads to substantial pricing errors. A first-order perturbation provides a sensible approximation to the effects of risk in continuous-time models. It reduces pricing errors by around 90% relative to the certainty equivalent linear approximation.

Technical Details

RePEc Handle
repec:eee:dyncon:v:133:y:2021:i:c:s0165188921001834
Journal Field
Macro
Author Count
3
Added to Database
2026-01-28