Prof. Dr. Johannes Breuer heads the “Research Data & Methods” team at CAIS. Together with the University of Duisburg-Essen, he was also appointed Professor of Digital Social Sciences.
His research focuses on:
- Use and effects of digital media
- Digital trace data
- Computational methods
- Meta-science
- Open science
Before joining CAIS, Johannes Breuer worked for eight years at GESIS – Leibniz Institute for the Social Sciences, most recently as Senior Researcher and Head of the “Digital Society Observatory” team. From 2021 to 2024, he built up the “Research Data & Methods” team at CAIS together with Prof. Katrin Weller. Previously, he held positions at the Universities of Cologne, Hohenheim, Münster, and at the Leibniz Institute for Knowledge Media in Tübingen.
Curriculum Vitae
- Since 09/2025: Professor for Digital Social Sciences at the University of Duisburg-Essen
- From 2017 to 2025: Senior Researcher at GESIS – Leibniz Institute for the Social Sciences
- From 2015 to 2017: Research associate (postdoc) in the ERC project “Redefining Tie Strength – How social media (can) help us to get non-redundant useful information and emotional support” (ReDefTie; project leader: Prof. Dr. Sonja Utz) at the Leibniz Institute for Knowledge Media (IWM) in Tübingen
- From 2014 to 2017: Postdoc at the Chair of Media and Communication Psychology (Prof. Dr. Gary Bente) at the University of Cologne
- 2013: Doctorate (Dr.phil.) in psychology at the University of Cologne
- From 2010 to 2014: Research assistant in the ERC project “The social fabric of virtual life: A longitudinal multi-method study on the social foundations of online gaming” (SOFOGA; project leader: Prof. Dr. Thorsten Quandt)” at the University of Hohenheim (2010 to 2012) and the Westfälische Wilhelms-Universität Münster (2012 to 2014)
- From 2007 to 2010: Research assistant in the EU project “Psychologically Augmented Social Interaction Over Networks” (PASION) at the Chair of Media and Communication Psychology (Prof. Dr. Gary Bente) at the University of Cologne
- 2007: Diploma in Media Studies (Media Psychology & Media Cultural Studies) at the University of Cologne

