Sunbelt XXXI International Network for Social Network ... - INSNA

Alliance Building In Civic NetworksDiani, MarioNetworks, Collective Action and Social MovementsAlliances, Collective Action, Political Networks, Interorganizational Networks, Voluntary AssociationsTHURS.AM1In this paper, I draw upon data on inter‐organizational relations in two British cities to explore alliance building between civic organizations. My analysisdevelops in three different steps. First, I chart the extent of alliances in which civic organizations are involved, and discuss how the amount of resourcescontrolled by civic organizations and their focus on local rather than national or broader agendas may affect their involvement in networks. Second, I look atthe factors that actors perceive as most relevant at facilitating or preventing alliance building. Finally, using QAP regressions, I evaluate how similarity anddissimilarity on a number of properties as well previous involvement in networks affect the chances of dyadic relations between civic organizations.An Actor‐oriented Model Of Obesity, Physical Activity, And Screen TimeShoham, David A.; Lamberson, PJ; Steh, David; Tong, LipingSocial Networks and HealthAdolescents, Homophily, Siena, Physical Activity, Peer Influence, ObesityFRI.PM1Recent studies have investigated the "contagion" of obesity within social networks, yet critics have questioned the ability of these models to distinguish peerinfluence from homophily. One promising alternative approach is the actor‐oriented model developed by Snijders et al. By simulating network and behavioraldynamics according to various rules, then fitting the resulting patterns of network and behavior change to empirical data, the actor‐oriented model yieldsparameter estimates for behavior that are adjusted for network selection (including homophily), and vice‐versa. We used data from the National LongitudinalStudy of Adolescent Health with 1 year of follow‐up, restricted to a racially homogeneous high school with complete network data (N=635; mean outdegree=4.0).Three obesity‐related measures were investigated for homophily and peer influence (average similarity with peers): body mass index (BMI,mean=22.9 kg/m2 at baseline), screen time (mean=15.0 hours/week); and a physical activity score (PA, range 0‐9; mean=3.8). R‐Siena was used for estimation;significance was defined as p