Friendship Paradoxes on Quora

Abstract

The “friendship paradox” is the statistical pattern that, in many social networks, most individuals’ friends have more friends on average than they do. This phenomenon has been observed in various real-world social networks, dating back to a seminal 1991 paper by S.L. Feld. In recent years, the availability of large volumes of data on online social networks has allowed researchers to also study generalizations of the core friendship-paradox idea to quantities other than connectivity. This has led to the finding that, in social networks such as Twitter, a typical person whom a randomly selected individual follows is usually a more active user and contributor than that individual. Here, we study friendship paradoxes on Quora, an online knowledge-sharing platform that is structured in a question-and-answer format. In addition to the “traditional” friendship paradoxes in the network of people following one another on Quora, we also study variants of the phenomenon that arise through the platform’s core interactions. We specifically focus on “upvoting” and “downvoting,” actions that people take to give positive and negative feedback on Quora answers. We observe that, for most answer authors who have few followers, for most of their answers, most of the upvoters of those answers have more followers than they do. This has potentially advantageous consequences for the distribution of content produced by these writers. Meanwhile, we also observe a paradox in downvoting: for most sufficiently active answer writers who got downvoted by other sufficiently active answer writers during a four-week period, most of their sufficiently active downvoters got downvoted more than they did. We explain how these paradoxes arise and place them in the context of recent research on friendship-paradox phenomena.