Nicholas A Christakis

Education

Christakis received a B.S. in biology from Yale University in 1984, where he won the Russell Henry Chittenden Prize. He received an M.D. from Harvard Medical School and an M.P.H. from the Harvard School of Public Health in 1989, winning the Bowdoin Prize on graduation.

In 1991, Christakis completed a residency in Internal Medicine at the University of Pennsylvania Health System. He was certified by the American Board of Internal Medicine in 1993. He obtained a Ph.D. in Sociology from the University of Pennsylvania in 1995. While at the University of Pennsylvania as a Robert Wood Johnson Clinical Scholar, he worked with Renee C. Fox, a distinguished American medical sociologist; other members of his dissertation committee were methodologist Paul Allison and physician Sankey Williams. In his dissertation, which was published as Death Foretold, Christakis studied the role of prognosis in medical thought and practice, documenting and explaining how physicians are socialized to avoid making prognoses. He argued that the prognoses patients receive even from the best-trained American doctors are driven not only by professional norms but also by religious, moral, and even quasi-magical beliefs (such as the "self-fulfilling prophecy").

Career

In 1995, Christakis started as an Assistant Professor with joint appointments in Departments of Sociology and Medicine at the University of Chicago. In 2001, he was awarded tenure in both Sociology and Medicine. He left the University of Chicago to take up a position at Harvard in 2001. Until July 2013, he was Professor of Medical Sociology in the Department of Health Care Policy and a Professor of Medicine in the Department of Medicine at Harvard Medical School; a Professor of Sociology in the Department of Sociology in the Harvard Faculty of Arts and Sciences; and an Attending Physician at the Harvard-affiliated Mt. Auburn Hospital.

In 2013, Christakis moved to Yale University, where he is a Professor of Sociology and a Professor of Medicine, with additional appointments in Evolutionary Biology and Biomedical Engineering.

From 2009 to 2013, Christakis and his wife, Erika Christakis, were Co-Masters of Pforzheimer House, one of Harvard's twelve residential houses. From 2015 to 2016, he served in a similar capacity at Silliman College at Yale University.

Research

Christakis uses quantitative methods (e.g., mathematical models of network formation, statistical analysis of large observational studies, and experiments) to study social networks and other social factors that affect health. His work has spanned the fields of demography, sociology, sociobiology, behavior genetics, network science, and biosocial science. He is an author or editor of four books, more than 180 peer-reviewed academic articles, numerous editorials in national and international publications, and at least three patents. His laboratory is also active in the development and release of software to conduct experiments and other studies (e.g., breadboard, Trellis).

Studies by Christakis and James H. Fowler suggested a variety of individuals' attributes like obesity, smoking, and happiness rather than being solely individualistic, also arise via contagion mechanisms that transmit these behaviors over some distance within social networks (see: "three degrees of influence"). Other work in the Christakis and Fowler labs has used experimental methods to study social networks, and has broadened to use many data sets and approaches. Christakis's Lab at has been supported by grants from the National Institutes of Health (NIH), by the Pioneer Program of the Robert Wood Johnson Foundation, by the Bill & Melinda Gates Foundation, and by other funders. In a TED talk, Christakis summarizes the broader implications of the role of networks in human activity.

In 2009, his group extended the study of social networks to genetics, publishing in Proceedings of National Academy of Sciences a finding that social network position may be partially heritable, and specifically that an increase in twins' shared genetic material corresponds to differences in their social networks. And in 2011, Fowler and Christakis published a follow-up paper on "Correlated Genotypes in Friendship Networks" in PNAS. Further work on this topic included "Friendship and Natural Selection" in PNAS in 2014. In 2012, in a paper in Nature, the group analyzed the social networks of the Hadza hunter gatherers, showing that human social network structure has ancient origins. Christakis and colleagues have also demonstrated that social networks are deeply related to human cooperation.

In 2010, Christakis and Fowler published a paper (based on the spread of H1N1 in Harvard University in 2009) regarding the use of social networks as 'sensors' for forecasting epidemics (of germs and other phenomena). In another TED talk, Christakis describes this effort (and computational social science more generally). A follow-up paper in 2014 documented the utility of this approach, again based on the "friendship paradox," using twitter data.

Beginning in 2010, Christakis and his colleagues initiated a program of research to deploy social networks to improve health and other social phenomena—for example, facilitating the adoption of public health innovations in the developing world, or demonstrating the utility of autonomous agents ("bots") in optimizing coordination in groups online.

Physician

Christakis has practiced as a home hospice physician, taking care of indigent, home-bound, dying patients in the South Side of Chicago. In Boston, from 2002 to 2006, Christakis worked as an attending physician on the Palliative Medicine Consult Service at Massachusetts General Hospital. In 2006, he moved to Mount Auburn Hospital, and in 2013, he moved to the Department of Medicine at Yale University.

Books

Christakis's first book, Death Foretold: Prophecy and Prognosis in Medical Care, was published by the University of Chicago Press in 1999.

Along with James Fowler, Christakis is the author of Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives, published in September 2009. It was awarded the "Books for a Better Life" Award in 2010 and has been translated into 20 languages. Connected draws on previously published and unpublished studies and makes several new conclusions about the influence of social networks on human health and behavior. In Connected, Christakis and Fowler put forward their "three degrees of influence" rule about human behavior, which theorizes that each person's social influence can stretch to roughly three degrees of separation before it fades out.

Christakis has also edited two clinical textbooks published by Oxford University Press.

Scientific papers

Free speech advocacy

While both at Harvard University and at Yale University, Christakis was involved in the defense of free expression. At Harvard, in 2012, he and his wife, Erika Christakis, came to the defense of minority students who were using satire to criticize the elite final clubs at that institution, and who the administration sought to punish. They suggested that the administration might be "more concerned with ugly words than the underlying problems," and that policing free expression on campus "denies students the opportunity to learn to think for themselves." Their argument expressed confidence in the capacity and maturity of Harvard students to discuss contentious issues.

At Yale, in 2015, they were involved in a controversy related to the regulation of Halloween costumes. On October 29, 2015, Christakis's wife Erika Christakis, a Lecturer on Early Childhood Education at the Yale Child Study Center, wrote an e-mail to Yale undergraduates on the role of free expression in universities, and arguing, from a developmental perspective, that students might wish to consider whether administrators should provide guidance on Halloween attire or whether students might wish to be allowed to 'dress themselves.' This e-mail was in response to a long earlier e-mail sent to undergraduates by administrators at Yale which encouraged students to be careful when choosing Halloween costumes, and provided links to recommended and non-recommended costumes. The e-mail played a role in substantial protests on campus that received national attention in the United States. Christakis and his wife were criticized by some Yale students for placing "the burden of confrontation, education, and maturity on the offended" in response to remarks they perceived as racially insensitive, but others pointed out that Erika Christakis was defending the rights to free expression of all Yale students and expressing confidence in them. Ninety-five Yale faculty members signed a letter supporting the Christakises; this letter noted that the Christakises distinguished support for freedom of expression from supporting the content of such expression and furthermore stated that "One can differ with her suggestion that administrative bodies should not play such an oversight role at Yale, but the suggestion itself clearly does not constitute support for racist expression." Despite Christakis' belief that Yale students could discuss controversial issues (such as costumes) among themselves, and his confidence in their ability to do so, he stepped down from his role at Silliman College at the end of the academic year, The Atlantic later noted.

In a subsequent Op-Ed in The New York Times, Christakis argued: "Open, extended conversations among students themselves are essential not only to the pursuit of truth but also to deep moral learning and to righteous social progress." A year later, commentators expressed concern about how students and faculty had behaved at Yale, and Erika Christakis described the circumstances that she had faced the preceding year in an op-ed published in October, 2016. The incident led to the labelling of some students as being members of Generation Snowflake. In April 2017, an episode of The Simpsons entitled "Caper Chase," mentioned the events, with one character saying: "We also need to hire more deans to decide which Halloween costumes are appropriate." Also in 2017, a short documentary was released about this episode, arguing that it reflected a collision between "old values" centered on reason and debate, on the one hand, and "administrative bloat" and a shift to a "consumer mentality" on the other (this documentary also noted that Christakis comes from a multi-racial family).

Personal

Christakis is married to early childhood educator and author Erika Christakis and they have three children. His hobbies have included Shotokan karate (his instructor, Kazumi Tabata, mentions him ) and making maple syrup.