Abstract

In his remarkably meticulous and even-handed 2005 book, Expert Political Judgment, Philip E. Tetlock establishes that the only thing we can count on in the political experts' predictions is that they will underperform-in some cases significantly-the predictions made by mechanical statistical procedures, including random chance. Experts have many uses and Tetlock does not claim that they have no value. However, Tetlock zeroes in on experts' important political role-as prognosticators. Tetlock does not attempt the impossible by trying to judge experts on their ability to prognosticate the effects of public policies; this would require that Tetlock himself could know what those effects were, and even in retrospect, it isn't that simple. Experts' failure to predict much simpler matters, however, such as GDP growth within a broad range, strongly suggests that technocracy is worse than putting dart-throwing chimps in charge of public policy