青少年友谊网络与受欺凌的共同变化关系：一项纵向社会网络分析研究

Bullying is a group process that involves multiple behaviors and multiagent interactions. However, few studies have focused on the development of bullying-related behaviors in the context of peer group interaction and relationship change, particularly in friendship networks. Although social support theory suggests that positive friendships act as a buffer, previous research has found that victims have difficulty making friends. Furthermore, recent research on friendship networks has indicated that the potential buffering role of friends may depend on the extent to which friends engage in certain behaviors. It is thus crucial to determine how victims shape their friendship networks and the protection mechanisms or detrimental effects associated with victims that such networks can trigger. Accordingly, the aim of this study was to longitudinally examine the selection and influence effects of victimization in dynamic classroom friendship networks using a sample of Chinese adolescents. We expected that (1) while peers tend to avoid selecting victims as friends (H1a: peer avoidance effect), victims tend to select other victimized youth as friends (H1b: peer selection effects), and that (2) the more friends that an adolescent has, the less he or she is victimized (H2a: peer protective effect), whereas one's victimization increases as a result of ones friends being victimized (H2b: peer influence effect). A total of 1406 eighth-grade students in public middle schools from Central China were recruited to participate in three assessments, with an interval of six months. Peer nomination was applied to evaluate friendship and victimization, with a maximum of five nominations allowed from classmates who fit the description. Capitalizing on longitudinal social network analysis (SIENA) to disentangle selection and influence processes, this study focuses on the role of friendship in adolescents peer victimization after controlling for structural characteristics of the network (e.g., transitivity and reciprocity) in friendship network dynamics. It was found that (1) while peers avoided selecting victims as friends (peer avoidance effect), victims tended to select other victims as friends (peer selection effect); (2) whether peers nominated others as friends was not influenced by their level of victimization; (3) having more friends decreased ones level of victimization (peer protection effect), while being friends with a victim increased ones possibility of being victimized over time (peer influence effect); (4) the higher the victimization level of an adolescent was, the higher his or her victimization level gradually rose over time (enhanced effect of victimization); and (5) the level of victimization decreased over time among girls compared to that of boys. These results revealed the peer selection and influence effects on the covariation of friendship networks and victimization among Chinese adolescents and demonstrated the peer contagion that is associated with victimization, which provides insights for interventions for school bullying.