Banning Foreign Pharmacies from Sponsored Search: The Online Consumer Response
研究了谷歌禁止未经NABP认证的药店参与赞助搜索后，消费者搜索和点击行为的变化，发现其他认证药店通过有机点击部分弥补了付费点击的损失，而未认证药店则面临更大挑战。
Increased competition from the Internet has raised concerns about the quality of prescription drugs sold online. Given the pressure from the Department of Justice, Google agreed to ban pharmacies not certified by the National Association of Boards of Pharmacy (NABP) from sponsored search listings. Using comScore click-through data originated from health-related queries, we study how the ban affects consumer search and click behavior in a difference-in-differences framework using the synthetic control method. We find that non-NABP-certified pharmacies received fewer clicks after the ban, and this effect is heterogeneous. In particular, pharmacies not certified by the NABP but certified by other sources (other-certified websites), experienced an increase in organic clicks that partially offset the loss in paid clicks after the ban. By contrast, pharmacies not certified by any certification agency experience much lower rates of substitution in organic clicks. These results suggest that the ban has increased the search cost for other-certified websites, but at least some consumers overcome the search cost by switching from sponsored to organic links. The lower substitution for uncertified websites may be explained by the rising consumer concerns about the quality of drugs sold on uncertified websites after the ban. Data and the online appendix are available at https://doi.org/10.1287/mksc.2017.1058 .