Econ Papers Daily / 期刊论文
最优简单评级
Optimal Simple Ratings
摘要
We study optimal simple rating systems that partition sellers into a finite number of tiers. We show that optimal ratings must be threshold partitions, and that for linear supply and Cournot competition with constant marginal cost, optimal thresholds solve a k-means clustering problem requiring only the quality distribution. For convex (concave) supply functions, optimal thresholds are higher (lower) than the k-means solution. For log-concave distributions, two-tier certification captures at least 50% of maximum welfare gains from full disclosure, with five tiers typically achieving over 90%. Applications to eBay and Medicare Advantage data illustrate our method.
中文摘要
我们研究将卖家划分为有限等级的最优简单评级系统。我们证明，最优评级必须是阈值划分，并且在线性供给和恒定边际成本的古诺竞争下，最优阈值解决一个仅需质量分布的k均值聚类问题。对于凸（凹）供给函数，最优阈值高于（低于）k均值解。对于对数凹分布，两层认证能捕获完全信息披露下最大福利收益的至少50%，而五层通常能达到90%以上。对eBay和Medicare Advantage数据的应用展示了我们的方法。