Work

Under-reaction: Irrational behavior or robust response to model misspecification?

Year: 2025
Type: article
Abstract: I find that under-reaction is a robust response to model misspecification, rewarded by financial markets, rather than an “irrational” attitude that leads to extinction. When a Bayesian agent trades with an under-reacting agent who has access to the same information, there are no paths on which the under-reacting agent loses all his wealth to the Bayesian. Conversely, the Bayesian agent loses all his wealth to the under-reacting agent in misspecified learning settings, provided that a combination of parameters is more accurate than any single parameter in the support, and the under-reaction is sufficiently strong.
Language: English
Subfield: Finance
Open Access status: hybrid
Estimated APC paid: $3,090
OpenAlex ID: W4413128952
FWCI: 1.878
Cites: 34
Cited by: 3
Related to: 10