How Social Networks Influence Attitudes: Social and Informational Effects of Attitude Heterogeneity and Arguments

University of Minnesota Ph.D. dissertation. August, 2008. Major: Mass Communication. Advisors: Daniel B. Wackman, Marco C Yzer. 1 computer file (PDF); xiv, 299 pages.This dissertation explores how social cues and information influence individual attitude strength within a social network context. It draws upon both cognitive and social perspectives from the attitude literature. In the study, participants were randomly assigned to: 1) a social condition (either a homogeneous social network where all other network members agreed, or a heterogeneous social network where half agreed and half disagreed with the participant’s own initial attitude), and 2) an informational condition (where the kind of information other network members shared either consisted of only opinions, or opinions supported by arguments). The study hypotheses were developed based on theories and empirical studies related to: attitude homogeneity (e.g., balance theory and consensus effects), attitude heterogeneity (e.g., two-sided messages), information processing, social comparison and inoculation processes. The study predicted that: a) those in attitudinally homogeneous networks would report higher attitude strength than those in heterogeneous networks, b) participants in networks where arguments are shared would report higher attitude strength than participants in network where opinions are shared, and c) an interaction effect would emerge such that for participants in homogeneous networks, there would not be a significant difference between opinion and argument networks on reported composite attitude strength, whereas for participants in heterogeneous networks, those in opinion networks would report lower attitude strength than those in argument networks. To test the research hypotheses, a computer experiment was developed where participants believed they were interacting with others, but in fact, responses were computer-generated, in order to control social network conditions to investigate their effect on participants’ attitudes. The experiment consisted of a 2 (Network Type: attitudinally homogeneous, attitudinally heterogeneous) x 2 (Network Information: opinions only, opinions and arguments) between-subjects design. Main study findings revealed a significant Network Type effect, but not a Network Information or Interaction effect. Additional analyses and discussion focus on whether additional variables, such as perceptions of other network members’ credibility, argument quality, and level of threat to one’s own attitude, help explain the primarily social, rather than informational, effects that emerged. Practical implications are discussed for strategic communication messaging, online social media and word-of- mouth marketing