In the e-learning context, social network analysis (SNA) can be used to build understanding around the ways students participate and interact in online forums. This study contributes to the growing body of research that uses statistical methods to test hypotheses about structures in social networks. Specifically, we show how statistical analysis can be used to examine the effect of students' past online interactions on their later participatory behavior, and to synthesize results across multiple networks. [This paper was published in: "Companion Proceedings 8th International Conference on Learning Analytics & Knowledge (LAK18)," 2018.]