人们如何选择保险计划

Economists ² often talk about "moral hazard," the idea that people's behavior changes in the presence of insurance. In finance, for instance, investors ³ may take more risks if they know they will be bailed ⁴ out, the subject of ongoing ⁵ political controversy ⁶. When it comes to health insurance, the existence of moral hazard is a more matter-of-fact issue: When people get health insurance, they use more medical care, as shown by research including a recent randomized study on the impact of Medicaid, which MIT economist ¹ Amy Finkelstein helped lead., ,Such evidence helps explain why insurers and policymakers looking to reduce overall costs have become increasingly attracted to the concept of "consumer-directed medical care," in which consumers pay for a larger share of medical expenses, sometimes in the form of high-deductible insurance plans. If people have to bear greater initial costs (the deductible（可减免的） is the amount consumers must pay before coverage ⁸ kicks in), they may be less likely to seek insured medical care for seemingly marginal health issues., ,But a new paper co-authored by Finkelstein suggests that forecasting the likely spending reduction associated with high deductibles requires a fine-grained approach, to account for the differing ways consumers respond to incentives ⁹ in the health-care market. The research indicates that consumers select insurance plans based not only on their overall wellness level -- with people in worse health opting ¹¹ for more robust ¹² coverage -- but also on their own anticipated response to having insurance., ,By scrutinizing ¹³ a large data set based on choices made by employees of Alcoa, Inc., the researchers found that consumers selecting a new insurance policy who expect to reduce their use of medical care by a lot if they have to pick up additional costs shy away from high-deductible plans; by contrast, the people who opt ¹⁰ for high-deductible plans are the ones who expect to change their health-care use the least., ,Thus insurers, or at least those who expect that offering more high-deductible plans will lower their expenses, may experience smaller spending changes than they might expect if a random ⁷ group of people were assigned to such plans., ,"What we [find] is that if you base your forecasts on random assignment, you would substantially overestimate ¹⁴ the spending reduction you can get by introducing high-deductible plans," says Finkelstein, the Ford ¹⁵ Professor of Economics at MIT. "The people who select these plans aren't randomly ¹⁶ drawn ¹⁷ from the population -- they tend to be people who have a lower behavioral response to the [insurance] contract."