Congressional Budget Office and National Bureau of Economic Research.
Q J Econ. 2012;127(1):199-235. doi: 10.1093/qje/qjr055.
Consumers need information to compare alternatives for markets to function efficiently. Recognizing this, public policies often pair competition with easy access to comparative information. The implicit assumption is that comparison friction—the wedge between the availability of comparative information and consumers' use of it—is inconsequential because when information is readily available, consumers will access this information and make effective choices. We examine the extent of comparison friction in the market for Medicare Part D prescription drug plans in the United States. In a randomized field experiment, an intervention group received a letter with personalized cost information. That information was readily available for free and widely advertised. However, this additional step—providing the information rather than having consumers actively access it—had an impact. Plan switching was 28% in the intervention group, versus 17% in the comparison group, and the intervention caused an average decline in predicted consumer cost of about $100 a year among letter recipients—roughly 5% of the cost in the comparison group. Our results suggest that comparison friction can be large even when the cost of acquiring information is small and may be relevant for a wide range of public policies that incorporate consumer choice.
消费者需要信息来比较不同的选择，以便市场有效运作。鉴于此，公共政策通常将竞争与易于获得比较信息相结合。隐含的假设是，比较摩擦——比较信息的可用性与消费者使用它之间的差距——是微不足道的，因为当信息易于获得时，消费者将访问这些信息并做出有效选择。我们考察了美国医疗保险处方药计划市场中比较摩擦的程度。在一项随机实地实验中，干预组收到了一封带有个性化成本信息的信。这些信息是免费的，并且广泛宣传。然而，提供信息而不是让消费者主动获取信息这一额外步骤产生了影响。干预组的计划转换率为 28%，而对照组为 17%，并且该干预措施导致收件人每年的预期消费者成本平均下降了约 100 美元，约为对照组成本的 5%。我们的结果表明，即使获取信息的成本很小，比较摩擦也可能很大，并且可能与许多纳入消费者选择的公共政策相关。
