Manoel Horta Ribeiro is a 5th year Ph.D. student in Computer Science at EPFL, Switzerland, advised by Professor Robert West. Previously, he received a MSc and BSc in Computer Science from UFMG, in Belo Horizonte, Brazil (where he was born and raised). His research focuses on understanding the impact of content moderation, recommender systems, and monetization in online platforms from a computational perspective. His work has been covered in outlets from El País to NBC News, in think tanks like the ICCT, and has shaped products in companies like Meta and Reddit. He is a Meta Computational Social Science Fellow, a Forbes 30 under 30 awardee, and has received awards for his teaching (from EPFL) and his research (from ACM conferences and Altmetrics).

Attend this talk via ZOOM


Online platforms like Facebook, Wikipedia, Amazon, and Linkedin are embedded in the very fabric of our society. They “curate content:” moderate, recommend, and monetize it, and, in doing so, can impact people’s lives positively or negatively. This talk will highlight the need to go beyond how these curation practices are currently designed and tested. I will argue that academic research can and should guide policy and best practices by discussing two projects I worked on during my doctorate.

First, I will describe a large natural experiment on Facebook that allowed measuring the causal effect of removing rule-breaking comments on users’ subsequent behavior. Second, I will present results on the efficacy of “deplatforming” Parler, a large social media website, on its users’ information diets. Finally, I will discuss future research directions on improving online platforms, emphasizing the opportunities and challenges posed by the popularization of generative AI. Altogether, my work indicates that we can improve online platforms—and, by extension, our lives—if we rigorously investigate the causal effect of content curation practices.