Econometrica · 2025 · [{"name": "Benjamin Vatter", "affiliation": ["Massachusetts Institute of Technology"]}]
中文摘要
政策制定者与市场中介机构常常利用质量评分来缓解有关产品质量的信息不对称。评分影响质量需求，并在均衡状态下影响质量供给。均衡效应打破了'信息越多总是越好'这一规则，评分的最优设计必须将其纳入考量。在 Medicare Advantage 的背景下，我发现消费者信息有限，且质量因低效而偏低。一种简单的设计方案缓解了这些问题，并使总福利增加了3.7个月保费。超过一半的收益源于评分对质量而非信息的影响。评分可以通过规制低效的寡头垄断质量供给而优于完全信息下的结果，一种二元质量认证即可实现该福利增益的98%。即使评分较为粗略，它们仍具有信息含量：企业的激励是在评分阈值处生产质量，而消费者对此知情。评分设计的核心挑战在于设定阈值，从而规制质量。
Abstract
Policymakers and market intermediaries often use quality scores to alleviate asymmetric information about product quality. Scores affect the demand for quality and, in equilibrium, its supply. Equilibrium effects break the rule whereby more information is always better, and the optimal design of scores must account for them. In the context of Medicare Advantage, I find that consumers' information is limited, and quality is inefficiently low. A simple design alleviates these issues and increases total welfare by 3.7 monthly premiums. More than half of the gains stem from scores' effect on quality rather than information. Scores can outperform full‐information outcomes by regulating inefficient oligopolistic quality provision, and a binary certification of quality attains 98% of this welfare. Scores are informative even when coarse; firms' incentives are to produce quality at the scoring threshold, which consumers know. The primary design challenge of scores is to dictate thresholds and thus regulate quality.