To mitigate adverse selection in insurance markets, individuals are often mandated to buy at least a baseline plan, but may choose to opt into a premium plan. In some markets, such as US health exchanges, each plan is responsible for the full expenses of those who buy it ("total pricing"). In other markets, such as the privately supplied "Medigap" top-ups to traditional government-provided Medicare, premium providers are only responsible for the incremental expenses they top up ("incremental pricing"). For parameter values calibrated to health exchanges, the shift from total to incremental pricing reduces the welfare loss from adverse selection by an order of magnitude.

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定价制度与逆向选择的福利成本

为了减轻保险市场中的逆向选择，个人通常被要求至少购买一个基准计划，但可能会选择加入保费计划。在某些市场，例如美国健康交易所，每个计划都负责购买者的全部费用（“总价”）。在其他市场，例如私人提供的“Medigap”充值到传统的政府提供的医疗保险，保费提供者只负责他们充值的增量费用（“增量定价”）。对于校准到健康交换的参数值，从总定价到增量定价的转变将逆向选择造成的福利损失减少了一个数量级。