Privacy and Marketing Externalities: Evidence from Do Not Call
利用美国“请勿来电”登记制度的执行时机，研究发现消费者登记行为对其他消费者产生了外部性：首波登记增加1%导致后续登记增加3.1%，且在大规模或教育/种族异质性高的市场更显著。
If not well targeted, advertising and direct marketing inflict nuisance and inconvenience on consumers. Theoretical analyses predict that consumer actions to avoid advertising impose externalities on other consumers. We investigate the extent of such externalities in the context of the U.S. Do Not Call (DNC) registry by exploiting the exogenous timing of the enforcement of the registry. Supported by multiple robustness tests, and validation and falsification exercises, we conclude that consumer DNC registrations imposed externalities on other consumers. An increase in the first wave of registrations by 1% was associated with a 3.1% increase in subsequent registrations. This effect was stronger in larger and more educationally or racially heterogeneous markets. The externality was possibly due to unregistered consumers being more receptive to telemarketing and telemarketers increasing calls to them. Our results suggest that managers should facilitate consumer opt-out, especially in larger and more educationally or racially heterogeneous markets. Data, as supplemental material, are available at http://dx.doi.org/10.1287/mnsc.2014.2051 . This paper was accepted by J. Miguel Villas-Boas, marketing.