Sandra González-Bailón: lead author with control rights; Annenberg School for Communication, University of Pennsylvania
E-mail: sandra.gonzalez.bailon@asc.upenn.edu
David Lazer: lead author with control rights; Network Science Institute, Northeastern University
E-mail: d.lazer@northeastern.edu
Pablo Barberá: lead Meta author; Meta
E-mail: us2020research@meta.com
William Godel: lead Meta author; Meta
E-mail: us2020research@meta.com
Hunt Allcott: Environmental and Energy Policy Analysis Center, Stanford University
E-mail: allcott@stanford.edu
Taylor Brown: Meta
E-mail: us2020research@meta.com
Adriana Crespo-Tenorio: Meta
E-mail: us2020research@meta.com
Deen Freelon: Annenberg School for Communication, University of Pennsylvania
E-mail: dfreelon@upenn.edu
Matthew Gentzkow: Department of Economics, Stanford University
E-mail: gentzkow@stanford.edu
Andrew M. Guess: Department of Politics and School of Public and International Affairs, Princeton University
E-mail: aguess@princeton.edu
Shanto Iyengar: Department of Political Science, Stanford University
E-mail: siyengar@stanford.edu
Young Mie Kim: School of Journalism and Mass Communication, University of Wisconsin-Madison
E-mail: ymkim5@wisc.edu
Neil Malhotra: Graduate School of Business, Stanford University
E-mail: neilm@stanford.edu
Devra Moehler: Meta
E-mail: us2020research@meta.com
Brendan Nyhan: Department of Government, Dartmouth College
E-mail: nyhan@dartmouth.edu
Jennifer Pan: Department of Communication, Stanford University
E-mail: jp1@stanford.edu
Carlos Velasco Rivera: Meta
E-mail: us2020research@meta.com
Jaime Settle: Department of Government, William & Mary
E-mail: jsettle@wm.edu
Emily Thorson: Department of Political Science, Syracuse University
E-mail: ethorson@gmail.com
Rebekah Tromble: School of Media and Public Affairs and Institute for Data, Democracy, and Politics, The George Washington University
E-mail: rtromble@email.gwu.edu
Arjun Wilkins: Meta
E-mail: us2020research@meta.com
Magdalena Wojcieszak: Department of Communication, University of California, Davis Center for Excellence in Social Science, University of Warsaw
E-mail: mwojcieszak@ucdavis.edu
Chad Kiewiet de Jonge: Meta research lead; Meta
E-mail: us2020research@meta.com
Annie Franco: Meta research lead; Meta
E-mail: us2020research@meta.com
Winter Mason: Meta research lead; Meta
E-mail: us2020research@meta.com
Natalie Jomini Stroud: co-last author and academic research lead; Moody College of Communication and Center for Media Engagement, University of Texas at Austin
E-mail: tstroud@austin.utexas.edu
Joshua A. Tucker: co-last author and academic research lead; Wilf Family Department of Politics and Center for Social Media and Politics, New York University
E-mail: joshua.tucker@nyu.edu
Acknowledgements: The Facebook Open Research and Transparency (FORT) team provided substantial support in executing the overall project. We are grateful for support on various aspects of project management from Chaya Nayak, Sadaf Zahedi, Lama Ahmad, Akshay Bhalla, Clarice Chan, Andrew Gruen, Bennet Hillenbrand, Pamela McLeod, and Dáire Rice; engineering and research management from Da Li and Itamar Rosenn; engineering from Yuxi Chen, Shiyang Chen, Tegan Lohman, Robert Pyke, and Yixin Wan; data engineering from Suchi Chintha, John Cronin, Devanshu Desai, Vikas Janardhanan, Yann Kiraly, Xinyi Liu, Anastasiia Molchanov, Sandesh Pellakuru, Akshay Tiwari, Chen Xie, and Beixian Xiong; data science and research from Hannah Connolly-Sporing; academic partnerships from Rachel Mersey, Michael Zoorob, Lauren Harrison, Simone Aisiks, Yair Rubinstein, and Cindy Qiao; privacy and legal assessment from Kamila Benzina, Frank Fatigato, John Hassett, Subodh Iyengar, Payman Mohassel, Ali Muzaffar, Ananth Raghunathan and Annie Sun; and content design from Caroline Bernard, Jeanne Breneman, Denise Leto, and Melanie Jennings. NORC at the University of Chicago partnered with Meta on this project to conduct the fieldwork with the survey participants. We are particularly grateful for the partnership of NORC Principal Investigator J.M. Dennis and NORC Project Director Margrethe Montgomery.