ORIGINS AND FRONTIERS OF BEHAVIORAL MACROECONOMICS – FROM (IR)RATIONALITY TO EXPECTATIONS
This paper examines the origins and current frontiers of behavioural macroeconomics, using expectation formation as a conceptual framework linking early psychological insights to modern formal models. The review traces developments from animal spirits, bounded rationality and adaptive expectations to heterogeneous heuristics, sticky information, rational inattention and behavioural New Keynesian models. Its main contribution is a comparative assessment of these approaches in terms of their underlying mechanisms, empirical predictions, identification challenges and implications for monetary and fiscal policy. Particular attention is given to heterogeneity stemming from different economic circumstances and to behavioural departures from rational expectations. The analysis shows that competing approaches can explain similar macroeconomic patterns yet imply different causal mechanisms and policy responses. Future progress depends on direct model comparisons, causal identification, out-of-sample validation and the integration of survey, experimental, administrative and high-frequency data into theoretically disciplined models.