Summary:

- The article discusses a response by Nicholas Christakis to criticisms of his research on the "contagion of obesity." Christakis is a physician and social scientist who has studied the spread of obesity and other health behaviors through social networks.

- Christakis addresses several common criticisms of his work, including the claim that the observed correlations in obesity within social networks are due to homophily (the tendency of people to associate with similar others) rather than true contagion. He argues that his research has accounted for homophily and still finds evidence of contagion effects.

- The article also notes that Christakis's work has been influential in the field of social network analysis and has implications for understanding the spread of various behaviors and outcomes through social connections.