Nicholas A. Christakis — American Scientist born on May 07, 1962,

Nicholas A. Christakis is an American sociologist and physician known for his research on social networks and on the socioeconomic and biosocial determinants of behavior, health, and longevity. He is the Sol Goldman Family Professor of Social and Natural Science at Yale University. He directs the Human Nature Lab, and he is the Co-Director of the Yale Institute for Network Science... (wikipedia)

We and others have done a bunch of work to show that if your real friends online say or do something, it affects you. But if your acquaintances online say or do something, it does not. People on average have about 106 Facebook friends, but only 5 or 6 real friends.
The social sciences offer equal promise for improving human welfare; our lives can be greatly improved through a deeper understanding of individual and collective behavior. But to realize this promise, the social sciences, like the natural sciences, need to match their institutional structures to today's intellectual challenges.
It is the spread of the good things that vindicates the whole reason we live our lives in networks. If I was always violent to you or gave you germs, you would cut the ties to me and the network would disintegrate. In a deep and fundamental way, networks are connected to goodness, and goodness is required for networks to emerge and spread.
We cannot understand our humanity just by studying individuals.
Social media and the Internet haven't changed our capacity for social interaction any more than the Internet has changed our ability to be in love or our basic propensity to violence, because those are such fundamental human attributes.