Social media platforms have become a central part of economic and social life: Billions of people connect, communicate, and create content online every day, and businesses increasingly depend on these platforms to reach customers, build brands, and co-create value. What constitutes the value of social media is the connections between their members and the resulting network structure. This network structure shapes how information, opinions, and behaviors spread – driving opportunities such as viral marketing and customer engagement, but also societal challenges such as the formation of echo chambers and the spread of fake news. Understanding social media therefore requires both an economic perspective on platform business models and a methodological perspective on how to analyze the underlying networks.

Building on a systematic understanding of social media platforms and their business models, we cover concepts and methods for modeling and analyzing social media as networks, as well as their applications in business and society. Topics in this course include an introduction to social media platforms and their business models, followed by the foundations of social network analysis: modeling social media as networks, characteristic properties of these networks, diffusion processes, centrality measures, and community detection. Building on these methods, we explore applications from a business perspective, such as social media marketing and the identification of influential users, as well as from a societal perspective, such as echo chambers, polarization, and the detection of fake news and disinformation. Throughout the course, students apply these methods to real-world social media data using appropriate software tools, interpret the results, and derive recommendations for action. Besides that content, the lecture entails first-hand research insights, exercises and discussion sessions.

Literature:

• Barabási, A.-L. (2015) Network Science, available at barabasi.com/networksciencebook/
• Borgatti, S. P.; Everett, M. G.; Johnson, J. C. (2013) Analyzing Social Networks. SAGE Publications Limited, London.
• Granovetter, M. S. (1973) The Strength of Weak Ties. In: American Journal of Sociology 78 (6), S. 1360-1380.
• Milgram, S. (1967) The small world problem. In: Psychology today 2 (1), S.60-67.
• Newman, M. E. J.; Girvan, M. (2004) Finding and evaluating community structure in networks. In: Physical Review E 69 (2), S. 026113:1-026113:15.
• Newman, M. E. J. (2010) Networks – An Introduction. Oxford University Press, Oxford.
• Wasserman, S.; Faust, K. (1994) Social Network Analysis: Methods and Applications. Cambridge University Press, Cambridge.
• Watts, D. J.; Strogatz, S. H. (1998) Collective dynamics of 'small-world' networks. In: Nature 393 (6684), S. 440-442.