Robert Shiller is best known for warning about the internet stock market bubble and later the housing bubble. What is most impressive to me, however, is that most people who think that markets can be inefficient are anti-market. Shiller’s solution to market problems, however, is more markets! The housing market, for example, has traditionally had two problems. Since each house is unique there has been no market index of housing prices so that people couldn’t easily see bubbles and if they could see them on the ground there was no easy way to short the market (to try to profit from the bubble in a way that would moderate the bubble). Moreover, because there haven’t been good housing indexes a very large amount of each average person’s wealth has been tied up with an asset that can fluctuate substantially in price. Most house buyers, in other words, are putting all their eggs in one basket and crossing their fingers that the basket doesn’t go bust. In recent years, that has been a very unfortunate bet.
Shiller’s solution to the problems in the housing market has been to make the market better—he created with Case and Weiss–the Case-Shiller Index. For the first time, it’s possible to see in real time housing prices and compare with averages over time and it possible to buy options and futures on the index which will help for forecasting. Moreover, it’s possible that in the future insurance products can be built based on local versions of the index–thus you could insure yourself against big declines in the price of housing in your neighborhood.
Shiller’s housing index is also a window into how macro markets could also be used to create livelihood insurance, a type of private unemployment insurance. Moral hazard and adverse selection make it difficult to protect any single individual from unemployment but indexes in the unemployment rate of dentists or construction workers could be used to provide some insurance for workers in these fields when conditions in their entire industry are poor.
I featured one of Shiller’s biggest ideas in Entrepreneurial Economics, markets in GDP. A GDP market would allow shares of GDP to be bought and sold, add to this Hansonian prediction markets and you are long way towards an ideal way to evaluate the effect of major policies. Moreover, a GDP market would allow the creation of many insurance products. We are all less diversified than is ideal. It would be optimal to trade some shares in US GDP for shares in World GDP which is more stable. We can do this if we create Shiller GDP markets throughout the world.
Shiller’s book Macro Markets is truly visionary and I hope the Nobel brings a lot of attention to these ideas.