Region: You've developed a significant body of work on asymmetric information in insurance markets, much of it with Amy Finklestein. In a recent paper with Amy and Casey Rothschild, “Redistribution by Insurance Market Regulation,” you estimate the efficiency costs and distributive impact of regulations that prohibit insurers from looking at buyer characteristics in determining prices. Are the cost and impact quantitatively significant? In an age when genetic testing is growing ever more sophisticated, what is the policy import of such findings?
Poterba: I am fascinated by insurance markets and the contracts that are available to individuals. This strikes me as an important and somewhat understudied area. My work with Amy and Casey tries to understand what happens when regulations preclude insurance companies from using some information to set insurance prices.
There are many examples of such regulations. Many states limit the data that firms can use to price automobile insurance. We consider the market for retirement annuities. In the United States, a firm cannot offer different pension payouts to men and women with the same salary history and years of service, retiring at the same age, even though life expectancy for women is several years longer than that for men at typical retirement ages.
In most settings, a ban on using some information to price insurance transfers resources toward those whom this information would show to be high-risk insurance buyers. In the market for annuities, someone who is expected to live a long time is more expensive to insure than someone who is unhealthy and has a high mortality risk. An insurance company could offer to pay higher monthly benefits to those who are ill or infirm if it could identify them. Sometimes insurance regulations make this difficult or impossible and therefore represent a transfer from one mortality risk group to another.
One of the intriguing questions is the extent to which insurance companies can induce policy buyers to reveal something about their underlying mortality type through the creative design of insurance policies. In Britain, insurers offer both inflation-indexed and nominal annuities. The households who buy the inflation-indexed products, which deliver more of their value at advanced ages than nominal products, tend to live longer than those who buy nominal annuities. This enables insurers to partly distinguish their client base. The extent to which such distinctions can be made is likely to vary across markets and settings.
Read the entire interview on the latest issue of The Region