Identifying peer effects in online communication behaviors

Tuesday, May 8, 2012 - 9:00am - 10:00am
Keller 3-180
Dean Eckles (Stanford University)
Peer effects can produce clustering of behavior in social networks, but so can homophily and common external causes. For observational studies, adjustment and matching estimators for peer effects require often implausible assumptions, but it is only rarely possible to conduct appropriate direct experiments to study peer influence in situ.

We illustrate the limitations of observational analysis with a constructed observational study that allows us to compare experimental and observational estimates of peer influence in link sharing via Facebook News Feed.

We describe research designs in which individuals are randomly encouraged to perform a focal behavior, which can subsequently influence their peers. Ubiquitous product optimization experiments on Internet services can be used for these analyses. This approach is illustrated with an analysis of peer effects in expressions of gratitude via Facebook on Thanksgiving Day 2010, with implications for the micro-foundations of culture.