Template-Type: ReDIF-Paper 1.0 Title: Feed for good? On the effects of personalization algorithms in social media platforms Author-Name: Miguel Risco Author-Email: risco@uni-bonn.de Author-Name: Manuel Lleonart-Anguix Author-Email: manuel.lleonart@bse.eu Classification-JEL: D43, D85, L15, L86 Keywords: personalized feed, social learning, network effects, interoperability Abstract: This paper builds a theoretical model of communication and learning on a social media platform, and describes the algorithm an engagement-maximizing platform implements in equilibrium. This algorithm overexploits similarities between users, locking them in echo chambers. Moreover, learning vanishes as platform size grows large. As this is far from ideal, we explore alternatives. The reverse-chronological algorithm that social platforms reincorporated after the DSA was enacted turns out to be insufficient, so we construct the "breaking-echo-chambers" algorithm, which improves learning by promoting opposite viewpoints. Finally, we advocate for horizontal interoperability as a regulatory measure to align platform incentives with social welfare. By eliminating platform-specific network effects, interoperability incentivizes platforms to adopt algorithms that maximize user well-being. Note: Length: 43 Creation-Date: 2024-08 Revision-Date: 2024-12 File-URL: https://www.crctr224.de/research/discussion-papers/archive/dp580 File-Format: application/pdf Handle: RePEc:bon:boncrc:CRCTR224_2024_580v2