Social signature in an online environment: Stability and cognitive limits

Abstract

Social tie maintenance has always had cognitive and emotional costs and has been leading to uneven distribution of communication volume among interaction partners of individuals. This distribution, known as social signature, is assumed to be stable for each person. Availability of digital traces of human communication allows testing whether this assumption is true and whether it holds in specific channels of computer-mediated communication. In this paper, we investigate private messaging on a popular social networking website on a sample of 39 users and 8063 communication partners of those users over the period of 18 months. We find that this communication channel does not reduce cognitive costs as the overall number of users' active contacts, on average, is equivalent to the cognitive limit known as Dunbar's number. Confirming some previous research, we show that the volume of communication is unevenly distributed, related to emotional closeness, and that changes in this distribution (that is, the changes in social signature) over time within an individual are smaller than the distances between social signatures of different individuals. However, as an absolutely novel finding, we demonstrate that the changes within individuals are statistically significant, thus questioning the concept of social signature as a stable phenomenon.