Does Mere Connection Lead to Social Interaction in Online Social Networks? An Empirical Investigation on Flickr.Com

Online social networks such as Twitter and Facebook have become increasingly popular. An interesting question is whether, once people become friends in these online social networks, they really influence each other. Although a stream of research has studied the social interaction effect, many of these studies employ a between-subjects design which complicates the identification of the effect. We address the question using a within-subjects design and a unique data set from Flickr.com, thereby reducing the identification challenge. Specifically, we examine whether people’s photo-marking decisions are influenced by their friends. Our findings reveal that friends do influence one another, though the influence is asymmetric: while an individual is more likely to mark a photo if her friends do so, she is much less affected if her friends take no action. We rule out one alternative explanation that this effect is driven by the influence of common friends. We show that the social interaction is enhanced by users’ offline closeness (measured by whether they live in the same country), but not affected by their characteristics in the social network. We also demonstrate the robustness of our findings against several assumptions made in the paper