Regularity and variability: Growth patterns of online friendships

Social network sites (SNSs) have brought revolutionary changes to individuals' social interactions. The growth of online personal relationships is crucial for understanding current interpersonal communications and network dynamics. In the context of a Chinese SNS, this study provides an empirical presentation of the growth patterns of individuals' online friendships. This study uncovers the regularity as well as the variability of such growth patterns. On the one hand, the friendship growth patterns show regularity in that the time trajectory of friendship growth for most users levels off at some point of their friendship formation. On the other hand, the growth patterns of online friendships also demonstrate variability. There are three essentially different growth patterns emerged: the logistic pattern (i.e., S-shape), the double-logistic pattern (i.e., double-S shape), and the power pattern (i.e., rotated-L shape). By employing multinomial logistic regression, this study further found that network connectedness lead to the differences in these growth patterns of online friendships. However, a user's personal strategy of online friendship formation is found to have a nil effect on explaining the differences in growth patterns of online friendships. This paper concludes by discussing the theoretical and practical implications of the growth patterns of online relationships.