I hope you are smiling!
“We found that social networks have clusters of happy and unhappy people within them that reach out to three degrees of separation. A person's happiness is related to the happiness of their friends, their friends' friends, and their friends' friends' friends—that is, to people well beyond their social horizon. We found that happy people tend to be located in the center of their social networks and to be located in large clusters of other happy people. And we found that each additional happy friend increases a person's probability of being happy by about 9%.
Happiness, in short, is not merely a function of personal experience, but also is a property of groups. Emotions are a collective phenomenon.” From Christakis & Fowler on EDGE
In this follow up, they parsed the photos of 1700 students on Facebook and looked for smiles. Yellow nodes are smilers; blue are frowners, and green go both ways.
“Statistical analysis of the network shows that people who smile tend to have more friends [and] are measurably more central to the network compared to those who do not smile. That is, if you smile, you are less likely to be on the periphery of the online world.”