Robert Shiller’s Nobel should help the world accept (and improve) imperfect financial markets

Can we avoid more economic casualties?
Can we avoid more economic casualties?
Image: Getty Images/Spencer Platt
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With the world still suffering from the 2008 financial crisis, it is good to see Nobel prizes going to three economists who have set the bar for analyzing how stock prices and other asset prices move in the real world: Eugene Fama, Robert Shiller, and Lars Hansen. Eugene Fama is best known for setting the benchmark for how financial markets would work in a world of perfect efficiency. Robert Shiller pointed out that financial markets look much less efficient at the macroeconomic scale of financial market booms and busts than they do at the microeconomic level of prices for individual stocks. And Lars Hansen developed the statistical techniques that have served as the touchstone for arbitrating between competing views of financial markets.

In many respects the “popular science” account of the work of Fama, Hansen and Shiller, given by the official Nobel prize website, is excellent. But its understated tone does not fully convey the drama of Fama and Shiller painting two diametrically opposed pictures of financial markets. (Nor the beauty and the clarity of Hansen’s way of thinking about the statistical issues in refereeing between these opposing views—but that would be too much to expect in a popular science treatment.) Fama’s picture of financial markets is Panglossian: all is for the best in the best of all possible worlds. In Shiller’s picture, financial markets are much more chaotic. As Berkeley economics professor and well-known blogger Brad DeLong puts it:

Financial markets are supposed to tell the real economy the value of providing for the future—of taking resources today and using them nor just for consumption or current enjoyment but in building up technologies, factories, buildings, and companies that will produce value for the future. And Shiller has, more than anyone else, argued economists into admitting that financial markets are not very good at this job.

Shiller’s view of financial markets that are swept up in successive excesses of optimism and pessimism allowed him to sound a warning of both the crash of the dot-com bubble in 2000 and the collapse of the house price bubble that interacted with high levels of leverage by big banks to bring down the world economy—to depths it still hasn’t recovered from.

Even when they don’t fully believe that all is for the best in the best of all possible worlds, the imaginations of most economists are captivated by the image of perfect markets, of which Eugene Fama’s Efficient Markets Theory provides an excellent example. The bad part about economists being riveted by the image of perfect markets is that they sometimes mistake this image for reality. The good part is that this image provides a wonderful picture of how things could be—a vision of a world in which (in addition to the routine work of facilitating transactions) financial markets gracefully do the work of:

  • information acquisition and processing,
  • getting funds from those who want to save to firms and individuals who need to borrow, and
  • sharing risks, so that the only risks people face are their share of the risks the world economy as a whole faces—except for entrepreneurs, who need to face additional risks in order to be motivated to do whatever they can to make their businesses successful.

One way to see how far the world is from fully efficient financial markets is that perfect markets would function so frictionlessly that the financial sector itself would earn income that was only a tiny fraction of GDP, where in the real world, “finance and insurance” earn something like 8% of GDP (see 1 and 2,) with many hedge fund managers joining Warren Buffett on Forbes’ list of billionaires.

One reason the financial sector accounts for such a big chunk of GDP may be that information acquisition and processing is much harder in the real world than in pristine economic models. After all, there is a strong tradition in economics for treating information processing (as distinct from information acquisition) as if it came for free. That is, look inside the fantasy world of almost all economic models, and you will see that everyone inside has an infinite IQ, at least for thinking about economic and financial decisions!

In the real world, being able to think carefully about financial markets is a rare and precious skill. But it is worse than that. Those smart enough to work at high levels in the financial sector are also smart enough to see the angles for taking advantage of regular investors and taxpayers, should they be so inclined. Indeed, two of the most important forces driving events in financial markets are the quest for plausible, but faulty stories about how the financial markets work that can fool legislators and regulators on the one hand and stories that can fool regular investors. A great deal of money made by those in the financial sector rides on convincing people that actively managed mutual funds do better that plain vanilla index funds—something that is demonstrably false on average, at least. And a surprisingly large amount of money is made by nudging regular investors to buy high-fee plain vanilla index funds as opposed to low-fee plain vanilla index funds. (There is a reason why for my retirement savings account I had to drill down to the third or fourth webpage for each mutual fund before I could see what fees it charges.) Even those relatively sophisticated investors who can qualify to put their money into hedge funds have been fooled by the hedge funds into paying not only management fees that typically run about 2% per year, but also “performance fees” averaging about 20% of the upside when the hedge fund does well, with the investor taking the full hit when the hedge fund does badly. So one crucial requisite for financial markets to do what they should be doing is for regular investors to know enough to notice when financial operators are taking them for a ride (which as it stands, is most of the time, at least to the tune of the bulk of fees paid) and when they are getting a decent deal.

For getting funds from those who want to save to those who need to borrow, the biggest wrench in the works of the financial system right now is that the government is soaking up most of the saving. The obvious part of this is budget deficits, which at least have the positive effect of providing stimulus for the economy in the short run. The less obvious part is that the US Federal Reserve is paying 0.25% to banks with accounts at the Fed and 0% on green pieces of paper when, after risk adjustment, many borrowers (who would start a business, build a factory, buy equipment, do R&D, pay for an education, or buy a house, car or washing machine) can only afford negative interest rates. (See “America’s huge mistake on monetary policy: How negative interest rates could have stopped the Great Recession in its tracks.”)

Yet, the departure from financial utopia that I find the most heart wrenching is the failure of real-world financial markets to share risks in the way they do in our theories. If financial markets worked as they should:

  • There would be no reason for the people in a banana republic to suffer when banana prices unexpectedly went down—that contingency would have been insured just as routinely as our houses have fire insurance,
  • There would be no reason for people to suffer if house prices unexpectedly went down in particular metropolitan areas more than elsewhere, since home price insurance built into mortgages would automatically adjust the size of the mortgage,
  • There would be no reason for people to suffer if the industry they worked in did unexpectedly badly, since that possibility would be fully hedged.

Some of these things don’t happen because people don’t understand financial markets well enough. But some don’t happen because the financial markets have not developed enough to offer certain kinds of insurance. All three winners this year richly deserve to be Nobel laureates. I tweeted the day before the announcement in favor of Robert Shiller because he, more than anyone else, has been trying to make financial markets live up to this vision of risk sharing. It not just that this is a big theme in the books he has written. Shiller has also patented new types of financial assets to enhance risk sharing and helped create the Case-Shiller home-price index as a foundation on which home-price insurance contracts could be based. Shiller’s vision of risk sharing is far from being a reality, but one day, maybe it will be. If that day comes, the world will look back on Robert Shiller as much more than a Nobel-Prize-winning economist. As Brad DeLong says of Shiller: “Pay attention to him.”

Follow Miles on Twitter at@mileskimball. His blog is