Imperfect Product Testing and Market Size
研究不完美的产品质量测试如何与逆向选择相互作用，影响市场规模。发现测试可能加剧逆向选择，且测试成本的小幅上升或测试精度的微小改进可能意外地提高某些卖家的预期利润，从而扩大市场。
We consider an imperfect test of product quality, and ask how it interacts with adverse selection to affect market size. Although one might expect adverse selection to be mitigated, there are scenarios where it is exacerbated. Also, two counter-intuitive comparative static results emerge. First, a small increase in the test cost can increase the equilibrium expected profits earned by sellers of higher quality units, and so expand the market. Second, the equilibrium expected profits earned by sellers with lower quality units can be increased by a small improvement in the accuracy of an imperfect test.