Optimal Contract Regulation in Selection Markets
研究了连续成本类型下的竞争性保险市场，监管者设定最低和最高保险覆盖水平以及非购买者费用，发现最优最低覆盖水平为正但低于全额保险，最优最高覆盖水平为全额保险，且非购买费用在类型密度递减时提高福利。
We model competitive insurance markets with continuous cost-types. A regulator sets minimum and maximum coverage levels and a fee for nonbuyers. Equilibrium is unique if the type distribution is log-concave. Increasing the nonpurchase fee increases welfare if the density of types is decreasing. The optimal level of the minimum coverage is positive, is below full insurance, and induces some pooling at the minimum coverage contract. The optimal level of the maximum coverage is full insurance, even in an extension that allows for ex post moral hazard.