Here is the Abstract:
Does the extent to which people are smiling in their Facebook photos predict future life satisfaction? In two longitudinal studies, the authors showed that smile intensity coded from a single Facebook profile photograph from male and female participants’ first semester at college was a robust predictor of self-reported life satisfaction 3.5 years later—as they were about to graduate from college. Controlling for first-semester life satisfaction, the authors also determined that smile intensity was a unique predictor of changes in life satisfaction over time. In addition, the authors demonstrated that the results were not due to extraversion or to sex differences in smile intensity. Finally, the authors showed that participants who exhibited a more intense smile in their Facebook photo had better social relationships during their first semester at college and that the association between smile intensity and life satisfaction 3.5 years later was partially mediated by first-semester social relationships satisfaction.
If you would like to read the full-text paper (at no cost), please see the instructions at the top left of this webpage.