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Prof. Dr. phil. Yannis Theocharis

E-Mail: yannis.theocharis(at)tum.de

 

Resume

Prof. Theocharis' (*1982) field of research is political behavior with a focus on how digital media impact political participation, communication, governance, and uncivil behavior in online spaces. His work deploys survey, experimental and computational methods to understand how social media changes the political information environment, empowers users by enabling new forms of political participation, but also demobilizes, marginalizes and polarize the public.

Prof. Theocharis studied Sociology at the University of Crete, New Media at the London School of Economics (LSE), and received his PhD in Political Science from University College London (UCL). Prior to his appointment as Chair for Digital Governance at TUM (2020), he was Alexander von Humboldt Fellow and Research Fellow at the Mannheim Centre for European Social Research (MZES), Assistant Professor at the University of Groningen, and Professor of Communication and Media with focus on Innovative Methods at the University of Bremen.

External Talks and Lectures

Yannis Theocharis delivers the keynote at the Political Communication Pre-conference at the 2025 Annual Meeting of the American Political Science Association

Yannis Theocharis delivered the keynote at the Political Communication Pre-conference at the 2025 Annual Meeting of the American Political Science Association. In the talk, he argued that social media platforms have a legitimacy problem when it comes to how they govern speech, and that this problem is not technical or local, but structural and political. From transparency deficits in platform guidelines, to the gap between user expectations and platform practice, to the export of US-centric speech norms into very different cultural contexts, these challenges directly affect the sovereignty of democratic choices. These are no longer just questions of platform design, but of democratic legitimacy itself. And they now have a profound impact on the workings and sovereignty of democracies around the world.

Winter Term 2025/26

Title TypeSWS
(POL10500) Fundamentals of Comparative Politics (Lecture)  VO2
(POL10500) Fundamentals of Comparative Politics (Exercise) SE2

Publications

2025

  • Castro, Laia; Theocharis, Yannis; Stępińska, Agnieszka; Hopmann, David Nicolas; Schemer, Christian; Aalberg, Toril; Cardenal, Ana Sofia; Corbu, Nicoleta; de Vreese, Claes; Esser, Frank; Koc-Michalska, Karolina; Matthes, Jörg; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Strömbäck, Jesper; Štětka, Václav; Van Aelst, Peter; Zoizner, Alon: How do Healthy Political Discussions Invigorate Online Participation? Evidence from 17 European Countries. Social Media + Society 11 (4), 2025 more…
  • Lühiste, Maarja; Praet, Stiene; Popa, Sebastian Adrian; Theocharis, Yannis; Barberá, Pablo; Fazekas, Zoltán; Tucker, Joshua A.: When Does Fame Not Matter? Examining Gender Differences in Politicians’ Social Media Experiences. Politics & Gender, 2025, 1–28 more…
  • Theocharis, Yannis; Kosmidis, Spyros; Zilinsky, Jan; Quint, Friederike; Pradel, Franziska: Content Warning: Public Attitudes on Content Moderation and Freedom of Expression. Content Moderation Lab at TUM Think Tank, OSF, 2025, more…
  • Zilinsky, Jan; Theocharis, Yannis: Conspiracism and government distrust predict COVID-19 vaccine refusal. Humanities and Social Sciences Communications 12 (1), 2025 more…
  • Zoizner, Alon; Matthes, Jörg; Corbu, Nicoleta; de Vreese, Claes H.; Esser, Frank; Koc-Michalska, Karolina; Schemer, Christian; Theocharis, Yannis; Zilinsky, Jan: Can AI-Attributed News Challenge Partisan News Selection? Evidence from a Conjoint Experiment. The International Journal of Press/Politics, 2025 more…

2024

  • Jin, Soyeon; Zilinsky, Jan; Pradel, Franziska; Theocharis, Yannis: Beliefs in Conspiracy Theories and Online News Consumption during the onset of the COVID-19 pandemic. Journal of Quantitative Description: Digital Media 4, 2024 more…
  • Pradel, Franziska; Zilinsky, Jan; Kosmidis, Spyros; Theocharis, Yannis: Toxic Speech and Limited Demand for Content Moderation on Social Media. American Political Science Review (Volume 118 Number 1), 2024, 1-18 more…
  • Tulin, Marina; Hameleers, Michael; de Vreese, Claes; Aalberg, Toril; Corbu, Nicoleta; Van Erkel, Patrick; Esser, Frank; Gehle, Luisa; Halagiera, Denis; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Mihelj, Sabina; Schemer, Christian; Stetka, Vaclav; Strömbäck, Jesper; Terren, Ludovic; Theocharis, Yannis: Why do Citizens Choose to Read Fact-Checks in the Context of the Russian War in Ukraine? The Role of Directional and Accuracy Motivations in Nineteen Democracies. The International Journal of Press/Politics, 2024 more…
  • Zapko‐Willmes, Alexandra; Theocharis, Yannis: Accounting for the association between socioeconomic status and youth political participation: A twin family study. Political Psychology, 2024 more…
  • Zilinsky, Jan; Theocharis, Yannis; Pradel, Franziska; Tulin, Marina; de Vreese, Claes; Aalberg, Toril; Cardenal, Ana Sofía; Corbu, Nicoleta; Esser, Frank; Gehle, Luisa; Halagiera, Denis; Hameleers, Michael; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Schemer, Christian; Štětka, Václav; Strömbäck, Jesper; Terren, Ludovic; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Van Aelst, Peter; Zoizner, Alon: Justifying an Invasion: When Is Disinformation Successful? Political Communication, 2024, 1-22 more…

2023

  • HAMELEERS, MICHAEL; TULIN, MARINA; DE VREESE, CLAES; AALBERG, TORIL; VAN AELST, PETER; CARDENAL, ANA SOFIA; CORBU, NICOLETA; VAN ERKEL, PATRICK; ESSER, FRANK; GEHLE, LUISA; HALAGIERA, DENIS; HOPMANN, DAVID; KOC‐MICHALSKA, KAROLINA; MATTHES, JÖRG; MELTZER, CHRISTINE; MIHELJ, SABINA; SCHEMER, CHRISTIAN; SHEAFER, TAMIR; SPLENDORE, SERGIO; STANYR, JAMES; STEPINSKA, AGNIESZKA; STETKA, VACLAV; STRÖMBÄCK, JESPER; TERREN, LUDOVIC; THEOCHARIS, YANNIS; ZOIZNER, ALON: Mistakenly misinformed or intentionally deceived? Mis‐ and Disinformation perceptions on the Russian War in Ukraine among citizens in 19 countries. European Journal of Political Research, 2023 more…

2022

  • Matthes, Jörg; Corbu, Nicoleta; Jin, Soyeon; Theocharis, Yannis; Schemer, Christian; van Aelst, Peter; Strömbäck, Jesper; Koc-Michalska, Karolina; Esser, Frank; Aalberg, Toril; Cardenal, Ana Sofia; Castro, Laia; de Vreese, Claes; Hopmann, David; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Štětka, Václav; Zoizner, Alon: Perceived prevalence of misinformation fuels worries about COVID-19: a cross-country, multi-method investigation. Information, Communication & Society, 2022, 1-24 more…
  • Theocharis, Yannis; Boulianne, Shelley; Koc-Michalska, Karolina; Bimber, Bruce: Platform affordances and political participation: how social media reshape political engagement. West European Politics, 2022, 1-24 more…
  • Zoizner, Alon; Sheafer, Tamir; Castro, Laia; Aalberg, Toril; Cardenal, Ana S.; Corbu, Nicoleta; de Vreese, Claes; Esser, Frank; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Schemer, Christian; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Štětka, Václav; Strömbäck, Jesper; Theocharis, Yannis; Van Aelst, Peter: The Effects of the COVID-19 Outbreak on Selective Exposure: Evidence from 17 Countries. Political Communication, 2022, 1-23 more…

2021

  • Aelst, Peter Van; Toth, Fanni; Castro, Laia; Štětka, Václav; de Vreese, Claes; Aalberg, Toril; Cardenal, Ana Sofia; Corbu, Nicoleta; Esser, Frank; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Schemer, Christian; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Strömböck, Jesper; Theocharis, Yannis: Does a Crisis Change News Habits? A Comparative Study of the Effects of COVID-19 on News Media Use in 17 European Countries. Digital Journalism, 2021, 1-31 more…
  • Castro, Laia; Strömbäck, Jesper; Esser, Frank; Aelst, Peter Van; de Vreese, Claes; Aalberg, Toril; Cardenal, Ana S.; Corbu, Nicoleta; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Schemer, Christian; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stepinska, Agnieszka; Štětka, Václav; Theocharis, Yannis: Navigating High-choice European Political Information Environments: A Comparative Analysis of News User Profiles and Political Knowledge. The International Journal of Press/Politics, 2021, 1-33 more…
  • Fazekas, Zoltán; Popa, Sebastian Adrian; Schmitt, Hermann; Barberá, Pablo; Theocharis, Yannis: Elite-public interaction on twitter: EU issue expansion in the campaign. European Journal of Political Research 60 (2), 2021, 376-396 more…
  • Heuer, Hendrik; Hoch, Hendrik; Breiter, Andreas; Theocharis, Yannis: Auditing the Biases Enacted by YouTube for Political Topics in Germany. Mensch und Computer 2021, ACM, 2021 more…
  • Schnaudt, Christian; van Deth, Jan W; Zorell, Carolin; Theocharis, Yannis: Revisiting norms of citizenship in times of democratic change. Politics, 2021, 1-18 more…
  • Schnaudt, Christian; van Deth, Jan W; Zorell, Carolin; Theocharis, Yannis: Revisiting norms of citizenship in times of democratic change. Politics, 2021, 026339572110317 more…
  • Theocharis, Yannis; de Moor, Joost: Creative Participation and the Expansion of Political Engagement. In: Oxford Research Encyclopedia of Politics. Oxford University Press, 2021 more…
  • Theocharis, Yannis; Cardenal, Ana; Jin, Soyeon; Aalberg, Toril; Hopmann, David Nicolas; Strömbäck, Jesper; Castro, Laia; Esser, Frank; Van Aelst, Peter; de Vreese, Claes; Corbu, Nicoleta; Koc-Michalska, Karolina; Matthes, Joerg; Schemer, Christian; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Štětka, Václav: Does the platform matter? Social media and COVID-19 conspiracy theory beliefs in 17 countries. New Media & Society, 2021, 146144482110456 more…
  • Theocharis, Yannis; Cardenal, Ana; Jin, Soyeon; Aalberg, Toril; Hopmann, David Nicolas; Strömbäck, Jesper; Castro, Laia; Esser, Frank; Van Aelst, Peter; de Vreese, Claes; Corbu, Nicoleta; Koc-Michalska, Karolina; Matthes, Joerg; Schemer, Christian; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Štětka, Václav: Does the platform matter? Social media and COVID-19 conspiracy theory beliefs in 17 countries. New Media & Society, 2021 more…
  • Theocharis, Yannis; Jungherr, Andreas: Computational Social Science and the Study of Political Communication. Political Communication 38 (1-2), 2021, 1-22 more…
  • Theocharis, Yannis; de Moor, Joost; van Deth, Jan W.: Digitally Networked Participation and Lifestyle Politics as New Modes of Political Participation. Policy & Internet 13 (1), 2021, 30-53 more…
  • Van Aelst, Peter; Toth, Fanni; Castro, Laia; Štětka, Václav; Vreese, Claes de; Aalberg, Toril; Cardenal, Ana Sofia; Corbu, Nicoleta; Esser, Frank; Hopmann, David Nicolas; Koc-Michalska, Karolina; Matthes, Jörg; Schemer, Christian; Sheafer, Tamir; Splendore, Sergio; Stanyer, James; Stępińska, Agnieszka; Strömbäck, Jesper; Theocharis, Yannis: Does a Crisis Change News Habits? A Comparative Study of the Effects of COVID-19 on News Media Use in 17 European Countries. Digital Journalism, 2021, 1-31 more…

2020

  • Boulianne, Shelley; Theocharis, Yannis: Young People, Digital Media, and Engagement: A Meta-Analysis of Research. Social Science Computer Review 38 (2), 2020, 111-127 more…
  • Kosmidis, Spyros; Theocharis, Yannis: Can Social Media Incivility Induce Enthusiasm? Public Opinion Quarterly 84 (S1), 2020, 284-308 more…
  • Kosmidis, Spyros; Theocharis, Yannis: Can Social Media Incivility Induce Enthusiasm? Public Opinion Quarterly 84 (S1), 2020, 284-308 more…
  • Kosmidis, Spyros; Theocharis, Yannis: Can Social Media Incivility Induce Enthusiasm?: Evidence from Survey Experiments. Public Opinion Quarterly 84 (S1), 2020, 284-308 more…
  • Theocharis, Yannis; Barberá, Pablo; Fazekas, Zoltán; Popa, Sebastian Adrian: The Dynamics of Political Incivility on Twitter. SAGE Open 10 (2), 2020, 215824402091944 more…
  • Theocharis, Yannis; Barberá, Pablo; Fazekas, Zoltán; Popa, Sebastian Adrian: The Dynamics of Political Incivility on Twitter. SAGE Open, 2020, 1-15 more…
  • Theocharis, Yannis; Jungherr, Andreas: Computational Social Science and the Study of Political Communication. Political Communication 38 (1-2), 2020, 1-22 more…

2018

  • Boulianne, Shelley; Theocharis, Yannis: Young People, Digital Media, and Engagement: A Meta-Analysis of Research. Social Science Computer Review 38 (2), 2018, 111-127 more…
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