Carnegie Mellon University


Social networks


We are all embedded in social networks, from the online variety to informal networks like friendship, physical contact, and kinship. These social networks have profound implications for how social dynamics unfold. Contact networks affect the progression of a disease. Misinformation spreads between friends. Social norms evolve by enforced conformity in a community. Our research focuses on the structure and dynamics of these social networks and how they affect our social lives.

Researchers: Nynke NiezinkCosma Shalizi, & Kevin Zollman

Understanding the emergence of sociality

man-dogs-800x800-min.jpgHumans are social creatures.  Our social behavior evolved from a complex intertwined process of cultural and biological evolution.  Behaviors like communication, cooperation, group formation, enforcement of social norms, and bargaining shape our social structure, and we share many of these behaviors with many non-human animals. Understanding the circumstances that gave rise to these behaviors helps us to understand both the world around us and ourselves. Research in this area helps us to uncover what gives rise to social behaviors, and what might lead to abrupt social change.

Researchers: Simon DeDeoRussell GolmanJohn Miller, & Kevin Zollman

The wisdom and madness of the crowd

crowd-800x800-min.jpgWe rely on collective wisdom for much of what we do. The “crowd” elects a political leader. The economy allocates goods and services to different people at different times. Yelp reviews steer us toward some restaurants and away from others. Despite this, crowds can be amazingly stupid. Phenomena like group think, discrimination, and war all result from crowds going awry.  They can be driven by identity based thinking, maladaptive social norms, and cognitive biases and processes to behave in remarkably counter-productive ways. Understanding when crowds are wise, and when they are not, is crucial to understanding much about our contemporary world.

Researchers: Simon DeDeoRussell Golman, John MillerNynke Niezink, Cosma Shalizi, & Kevin Zollman

Responding to information

newspaper-800x800-min.jpgOur social world is awash in information. Every day, we learn about current events, scientific discoveries, and the everyday lives of our friends (and celebrities). How we process that information and respond to it determines the course of history. Do we believe misinformation and pass it on? Does dialog change our mind? When do we seek out potentially unsettling information and when do we avoid it? Our research uncovers how people process, share, and seek information, and shows us how this affects large-scale social dynamics.

Researchers: Simon DeDeo & Russell Golman

Connecting the cognitive and the social

protest-800x800-min.jpgGroups are made up of individuals who make decisions using many interconnected cognitive processes.  Understanding how those processes shape social dynamics is critical for understanding why groups behave as they do and how we might influence them for the better.  Research in this area connects together insights from the study of individual behavior (especially from psychology and behavioral economics) and larger scale social behavior.

Researchers: Simon DeDeo & Russell Golman