A Nobel for Shiller
posted by Frank Pasquale
When I read Robert Shiller’s Finance and the Good Society last year, I had a sense the author treated the work as the penultimate step in a scholarly cursus honorum, to culminate in the Nobel. Thus my cautionary note in this review:
[Shiller] has eloquently analyzed the role of human psychology in markets, and he predicted both the tech and housing bubbles. He has been a methodological trailblazer, introducing behavioral science to the ossified academic discipline of finance. Time’s Michael Grunwald has called him a “must-read” among wonks in the Obama Administration. Shiller’s past books command respect and repay close reading. Given his sterling career, it is deeply disappointing to see Shiller divert the “behavioral turn” in economics into the apologetics of Finance and the Good Society.
As I explain in the review, in Finance and the Good Society Shiller engages in the cardinal sin of celebrity economists: he presumes to comment authoritatively on legal, poltical, and moral matters far from his real domain of expertise. As for co-winner Eugene Fama’s contributions, Justin Fox’s work is useful (as summarized in this 2009 review):
Eugene Fama . . . promulgated the efficient markets hypothesis in its most widely recognised form by combining it with the capital asset pricing model that portrays investing as a trade-off between risk and return. . . . [I]n the early 1990s, Fama and Kenneth French published a large empirical survey of stock market returns since 1940 and found several ways in which returns were not random and which could not be explained by [Fama's theory]. In aggregate, smaller companies did better than larger ones, while “value” stocks, which are cheap compared with the book value on their balance sheet, also outperformed. There was even a “momentum” effect – stocks that had been doing well for a while tended to continue to do so. . . . . Fox makes clear that this was tantamount to the founder of efficient markets admitting his theory was wrong and quotes the judgment of one critic: “The Pope said God was dead.” He is also scathing about Fama’s attempt to rescue the theory by categorising all these effects as “risk factors”. . . . All of this came more than a decade before last year’s implosion. So why did regulators continue to enshrine assumptions of efficiency in the rules they set?
The person who can answer that last question truly deserves a Nobel.