Human beings choose their friends, and often their neighbors and co-workers, and we inherit our relatives; and each of the people to whom we are connected also does the same, such that, in the end, we assemble ourselves into large-scale, face-to-face social networks. Why do we do this? And how might a deep understanding of human social network structure and function be used to intervene in the world to make it better? Here, I review research from our lab describing three classes of interventions involving both offline and online networks that can help make the world better: (1) interventions that rewire the connections between people; (2) interventions that manipulate social contagion, facilitating the flow of diverse phenomena within groups; and (3) interventions that manipulate the position of people within network structures. I illustrate what can be done using a variety of experiments in settings as diverse as fostering cooperation or innovation in networked groups online to fostering widescale behavior change in developing world villages and other settings. I also discuss experiments with “hybrid systems” comprised of humans and simple artificial intelligence (AI) agents interacting in small groups. Overall, by taking account of people's structural embeddedness in social networks, and by understanding social influence, it is possible to intervene in populations to enhance desirable properties as diverse as health, wealth, cooperation, coordination, and learning.
March 26, 2025 | 12:00-1:00PM
About the Speaker
Nicholas A. Christakis, MD, PhD, MPH, is the Sterling Professor of Social and Natural Science at Yale University. His work is in the fields of network science and biosocial science. He directs the Human Nature Lab and is the Co-Director of the Yale Institute for Network Science. He was elected to the National Academy of Medicine in 2006; the American Association for the Advancement of Science in 2010; the American Academy of Arts and Sciences in 2017; and the National Academy of Sciences in 2024.
