When economists skip over real-world complications, it’s as if physicists spoke of a world without gravity.
When the 2013 Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel (colloquially known as the “Economics Nobel”) was awarded to Eugene Fama and Robert Shiller, along with Lars Peter Hansen, many were puzzled by the selection. Fama and Shiller are both distinguished and highly regarded scholars, so it was not their qualifications that raised eyebrows. What seemed odd was that the committee had picked them together.
After all, the two economists seem to hold diametrically opposed views on how financial markets work. Fama, the University of Chicago economist, is the father of the “efficient market hypothesis,” the theory that asset prices reflect all publicly available information, with the implication that it is impossible to beat the market consistently. Shiller, the Yale economist, meanwhile, has spent much of his career demonstrating financial markets work poorly: they overshoot, are subject to “bubbles” (sustained rises in asset prices that cannot be explained by fundamentals), and are often driven by “behavioral” rather than rational forces. Could both these scholars be right? Was the Nobel committee simply hedging its bets?
While one cannot read the jury’s mind, its selection highlighted a central feature of economics—and a key difference between it and the natural sciences. Economics deals with human behavior, which depends on social and institutional context. That context in turn is the creation of human behavior, purposeful or not. This implies that propositions in economic science are typically context-specific, rather than universal. The best, and most useful, economic theories are those that draw clear causal links from a specific set of contextual assumptions to predicted outcomes.READ MORE>