Macroeconomics

Quantum mechanics

Linguistics

Perfect information

Philosophy

Microeconomics

Operating system

Economics

Computer science

Neoclassical economics

Keynesian economics

Physics

Computational economics

Rational agent

Macroeconomic model

Artificial intelligence

Agent-based model

Mathematical economics

Imperfect

Action (physics)

Rational expectations

Heuristics

Economic Inquiry

We analyze the individual and macroeconomic impacts of heterogeneous expectations and action rules within an agent‐based model populated by heterogeneous, interacting firms. Agents have to cope with a complex evolving economy characterized by deep uncertainty resulting from technical change, imperfect information, coordination hurdles, and structural breaks. In these circumstances, we find that neither individual nor macroeconomic dynamics improve when agents replace myopic expectations with less naïve learning rules. Our results suggest that fast and frugal robust heuristics may not be a second‐best option but rather “rational” responses in complex and changing macroeconomic environments. ( JEL C63, D8, E32, E6, O4)

RATIONAL HEURISTICS? EXPECTATIONS AND BEHAVIORS IN EVOLVING ECONOMIES WITH HETEROGENEOUS INTERACTING AGENTS