We study how strangers become friends within an evolving online social network. By modeling the co-evolution of individual users' friendship tie formations and their concurrent online activities (product adoptions and content generation), we are able to discover important drivers underlying...

We quantify the effects of others' adoptions and word-of-mouth (volume and valence) on consumers' product adoption decisions. We differentiate between the effects of word-of-mouth and observed adoptions from friends ("personal network") and the effects of word-of-mouth and observed adoptions...

We leverage a temporary block of the Chinese microblogging platform Sina Weibo due to political events, to estimate the causal effect of online word-of-mouth content on product demand in the context of TV show viewership. Based on this source of exogenous variation, we estimate an elasticity of...