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Network science is a growing field of interest ranging from sociology to physics. A primary goal of this field is to understand how the connectedness of a population (the topological structure of social ties) affects whether, and how fast, information, diseases, and behaviors will spread. My research on the dynamics of diffusion across social networks has implications for developing public health interventions, promoting products, and understanding cultural diffusion and social integration.

Norms and Collective Action

Are norms always functional? My research on norms and collective action studies the dynamics through which communities “lock in” to social norms. Sometimes norms promote cooperation for the public good, other times they can force people into undesirable “social traps,” and even de-stabilize collective action.

Social Epidemiology

Social dynamics can significantly impact the emergence and exacerbation of health inequalities, the spread of diseases, and changes in attitudes toward public health messages.  My research develops new methodologies for causally identifying how manipulations of social structure can systematically, and unexpectedly, alter the trajectory of population health.



Social Media and the Science of Health Behavior (posting soon)
Circulation (forthc. 2013)
Damon Centola
The recent explosion of social media provides significant new opportunities for health researchers to study how social interactions affect the dynamics of behavior change.

A Simple Model of Stability in Critical Mass Dynamics
Journal of Statistical Physics (2013)
Damon Centola
While strong social incentives, such as peer-enforcement, can facilitate the growth of collective action and collective behavior, these incentives can also compromise the dynamics of long term stability.

Homophily, Networks and Critical Mass:  Solving the Start-up Problem in Large Group Collective Action
Rationality and Society (2013)
Damon Centola
We demonstrate how a classic problem of rationality - the mobilization of voluntary collective action in "large groups" - can be solved when homophily and social networks foster the growth of critical mass coalitions.

An Experimental Study of Homophily in the Adoption of Health Behavior (Supporting Materials)
Science (2011)
Damon Centola
Experimental results demonstrate how homophily in social networks improves the diffusion of health behaviors.

The Spread of Behavior in an Online Social Network Experiment (Supporting Materials)
Science (2010)
Damon Centola
Experimental results show that behaviors spread farther and faster through clustered-lattice networks than through 'randomized' networks.
     • Awarded 2011 Best Article in Mathematical Sociology, American Sociological Association
     • Awarded 2011 Goodwin Award for Outstanding Contribution to Sociological Methodology, American Sociological Association

Failure in Complex Social Networks
Journal of Mathematical Sociology (2009)
Damon Centola
Scale-free networks can be far more vulnerable to failure due to random attacks than more homogeneously distributed exponential networks.

Homophily, Cultural Drift, and the Co-Evolution of Cultural Groups
Journal of Conflict Resolution (2007)
Damon Centola, Juan Carlos Avella, Victor Eguiluz, and Maxi San Miguel
Allowing networks to evolve endogenously provides a mechanism for understanding how the "homogenizing" forces of homophily and social influence can produce cultural diversity.

Complex Contagions and the Weakness of Long Ties
American Journal of Sociology (2007)
Damon Centola and Michael Macy
When behavioral adoption requires peer reinforcement, adding weak ties to a social network can actually slow down (and even prevent entirely) the diffusion process.
     • Awarded 2009 Best Article in Mathematical Sociology, American Sociological Association

Cascade Dynamics of Complex Propagation
Physica A (2007)
Damon Centola, Victor Eguiluz, and Michael Macy
Randomizing permutations on ordered social networks can cause phase transitions in the collective dynamics of diffusion.

The Emperor's Dilemma:  A Computational Model of Self-Enforcing Norms
American Journal of Sociology (2005)
Damon Centola, Robb Willer, and Michael Macy
We investigate how normative behaviors that can be detrimental to everyone in a population can nonetheless wind up not only spreading, but also being enforced by every member of the population.
• Awarded 2006 Best Article in Mathematical Sociology, American Sociological Association