Trellis is a suite of software tools for developing, administering, and collecting survey and social network data.  What separates Trellis from other survey tools is its support for mapping social networks and its ability to integrate them with survey data.

You can use Trellis to conduct a photographic census of the respondent population in sociocentric study designs. Then it’s possible to document the edges of the network by asking customized “name generator” questions such as “With whom do discuss important matters?”

An especially valuable feature of Trellis is that the respondents can identify their social contacts not only by name, but by photograph. This allows for accurate mapping of social networks even in low-literacy populations or where names may be similar or confusing. 

Network Science Improving Health in Honduras (video)

Can network science be used to improve health more cost-effectively in the developing world? We believe that because people are connected, their health is connected. Can social networks be utilized to influence behavior and, more importantly, be leveraged to achieve positive outcomes? To study this concept, researchers in the Human Nature Lab are spearheading a public health research study in Honduras, trying to map the extent to which improvements in health behaviors can ripple through social connections. The goal of the project, funded by the Bill and Melinda Gates Foundation, is to evaluate the effectiveness of using social network strategies to implement maternal and neonatal health interventions in rural settings. In the videos below (one short and one long) we discuss our driving motivations, our research design details, and our goals for the project. Please watch!


Breadboard is a software platform for developing and conducting human interaction experiments on networks. It allows researchers to rapidly design experiments using a flexible domain-specific language and provides researchers with immediate access to a diverse pool of online participants. To learn more about Breadboard, please visit

In a game of wealth, fat cats who don’t share keep winning

PBS Newshour: An online game asks players to share some of their wealth on faith that the others will reciprocate. But each player has the option of choosing not to share, amassing more and more wealth. In designing a game to test human behaviors that fuel economic inequality, Yale University researchers are finding that the poor stay poor and the rich stay rich. Economics correspondent Paul Solman reports.

Does the secret to social networking lie in the remote jungle?

The Human Nature Lab is conducting research in Honduras on social networks, trying to map the true extent to which one’s connectivity can influence behavior and, more importantly, be leveraged to achieve positive outcomes. This large scale project involving 160 villages in rural Honduras, with 40,000 people, is lead by Nicholas Christakis and James Fowler, and backed by the Gates Foundation. Read more: Does the secret to social networking lie in the remote jungle?

The Dangers of Visible Inequality

Many commentators have pointed to disturbances in Ferguson and elsewhere over the past year as proof that economic inequality leads to tensions and even violence. But new research out from the Human Nature Lab at the Yale Institute for Network Science suggests that it’s not the presence of inequality that causes problems, but rather the visibility of that inequality. Read more.

Click here to read the paper published in Nature.

Through the Wormhole

Through the Wormhole with Morgan Freeman filmed a segment in the Human Nature Lab  for their episode, ‘Are we all bigots?’ Evolution has hard-wired us toward subconscious bias. This episode explores how one can overcome bigotry through exposure, self-awareness, flexible social networks and violent video games. The HNL is featured briefly in the clip below and throughout the full episode.


Nature, nurture, or network?

Your friends and family influence your drinking, sleep, weight, and happiness—more than you think. Our work demonstrating the contagious nature of everything from obesity to altruism has stirred up considerable debate in the research world. It has also suggested powerful new ways to intervene in networks—for instance, to speed the switch to generic drugs, or to slow the spread of sexually transmitted diseases. Read more: