Due to technological innovation, news platforms such as Google News and all social media platforms have detailed information about their users. They sell access to highly targeted groups of users (=voters) to all kinds of political interest groups, including political parties but also many groups whose stated or true objectives are not transparent to users.

In technical terms, via such platforms political interest groups can (i) microtarget news based on individual-level voter data and (ii) obfuscate their identities, which can be exploited to spread disinformation. Together with Freek van Gils and Wieland Müller, we experimentally study the implementation of two proposed policy interventions aiming to counter the negative effects of microtargeting and voter obfuscation in the lab. By varying the media environments by which senders/political interest groups can send messages to receivers/voters, we find that mandatory disclosure of interests, with or without a microtargeting ban, increases the effciency of aggregate voter decision-making. However, only the combination of disclosure of interests and a microtargeting ban mitigates sender influence in this stylized voting environment. The implementation of a microtargeting ban without disclosure requirements has adverse effects.

The paper titled “Microtargeting and Voters’ Unawareness: Experimental Results” has appeared in the European Journal of Political Economy.