If you could accurately predict how share prices would move, you’d probably be quite wealthy. If you could offer insight that helps analysts and investors do a better job predicting such things, you might win the Nobel Prize. That’s what happened last week when American economists Eugene Fama and Lars Peter Hansen from the University of Chicago, and Robert Shiller from Yale University, jointly received the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel 2013. They were recognised for their empirical analysis of asset prices.
Eugene Fama is best known for his work on the efficient frontier which demonstrated stock prices are extremely difficult to predict over the short term because new information is incorporated into prices very quickly. His research not only influenced future research, many credit the emergence of Index-linked investments to his theories.
Robert Shiller, a student of behavioral economics, challenged Fama’s efficient markets hypothesis with the belief that markets are driven by human psychology which can and does create large and sustained pricing errors. Shiller established when the ratio of prices to dividends for stocks is high, prices tend to fall, and when the ratio is low, prices tend to increase.
Lars Peter Hansen developed the Generalised Method of Moments, or GMM, which proposed a “straightforward way to test the specification of the proposed model… Hansen’s work is instrumental for testing the advanced versions of the propositions of Fama and Shiller… If you want to do serious analysis of whether changing risk premia can help rationalise observed asset price movements, Hansen’s contributions will prove essential.”
According to the Nobel committee, “There is no way to predict the price of stocks and bonds over the next few days or weeks. But, it is quite possible to foresee the broad course of these prices over longer periods, such as the next three to five years… The Laureates have laid the foundation for the current understanding of asset prices. It relies in part on fluctuations in risk and risk attitudes, and in part on behavioral biases and market frictions.”