Are Bubbles Inevitable?
Judging from the results in the far-more-predictable circumstances of lab experiments, it seems so. My new Atlantic column looks at the research:
In these uncertain economic times, we'd all like a guaranteed investment. Here's one: it pays a 24-cent dividend every four weeks for 60 weeks, 15 dividends in all. Then it disappears. Unlike a bond, this security has no redemption value. It simply provides guaranteed dividends. It involves no tricky derivatives or unknown risks. And it carries absolutely no danger of default. What would you pay for it?
Before financially sophisticated readers drag out their calculators, look up interest rates, and compute the present value of those future payments, I have a confession to make. You can't buy this security, and it doesn't really pay dividends every four weeks. It pays every four minutes, in a computer lab, to volunteers in economic experiments.
For more than two decades, economists have been running versions of the same experiment. They take a bunch of volunteers, usually undergraduates but sometimes businesspeople or graduate students; divide them into experimental groups of roughly a dozen; give each person money and shares to trade with; and pay dividends of 24 cents at the end of each of 15 rounds, each lasting a few minutes. (Sometimes the 24 cents is a flat amount; more often there's an equal chance of getting 0, 8, 28, or 60 cents, which averages out to 24 cents.) All participants are given the same information, but they can't talk to one another and they interact only through their trading screens. Then the researchers watch what happens, repeating the same experiment with different small groups to get a larger picture.
The great thing about a laboratory experiment is that you can control the environment. Wall Street securities carry uncertainties—more, lately, than many people expected—but this experimental security is a sure thing. "The fundamental value is unambiguously defined," says the economist Charles Noussair, a professor at Tilburg University, in the Netherlands, who has run many of these experiments. "It's the expected value of the future dividend stream at any given time": 15 times 24 cents, or $3.60 at the end of the first round; 14 times 24 cents, or $3.36 at the end of the second; $3.12 at the end of the third; and so on down to zero. Participants don't even have to do the math. They can see the total expected dividends on their computer screens.
Here, finally, is a security with security—no doubt about its true value, no hidden risks, no crazy ups and downs, no bubbles and panics. The trading price should stick close to the expected value.
At least that's what economists would have thought before Vernon Smith, who won a 2002 Nobel Prize for developing experimental economics, first ran the test in the mid-1980s. But that's not what happens. Again and again, in experiment after experiment, the trading price runs up way above fundamental value. Then, as the 15th round nears, it crashes. The problem doesn't seem to be that participants are bored and fooling around. The difference between a good trading performance and a bad one is about $80 for a three-hour session, enough to motivate cash-strapped students to do their best. Besides, Noussair emphasizes, "you don't just get random noise. You get bubbles and crashes." Ninety percent of the time.
So much for security.
Read the rest here.