Abstract
<jats:p>We study the drivers of like-minded and low-reliability news-following on social media, and the effectiveness of interventions targeting them. In a five-week field experiment with more than 3,000 U.S. Facebook users, we document the passive nature of participants' news portfolio formation process and the role of behavioral frictions. The experiment varies whether participants are prompted to re-optimize the portfolio of news pages they follow on Facebook through a user-friendly platform-integrated interface, and whether they receive personalized information about outlet slant and reliability. In contrast to canonical models of news consumption, we find that the re-optimization interface induces large portfolio changes even without new information, while information alone has no effect unless paired with re-optimization. Our interventions produce two main effects: they reduce the slant and increase the reliability of users' portfolios, thus potentially mitigating negative externalities for democracy, and they move users' portfolios closer to their stated preferences, mitigating internalities.</jats:p>