Excessive Ambitions

Abstract

The current financial crisis has brought out a fatal flaw in the foundations of the economic theories that guided economic agents and regulators: the unwarranted claim to precision and robustness. In this article I try to diagnose this flaw and discuss possible remedies. I argue that actual agents are intrinsically less sophisticated than the models assume they are, and that the various proposals to sustain the models by appealing to as-if rationality all fail. I next consider behavioral economics as an alternative to the standard models, claiming that while they may allow for successful retrodiction, they do not hold out much promise for prediction. I also discuss the use of statistical models, arguing that they are subject to so many traps and pitfalls that only a handful of elite practitioners can be trusted to use them well. Finally, I offer some speculations to explain the persistence in the economic profession and elsewhere of these useless or harmful models.

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