| One of the fundamental regularities of human behavior is the interdependency of attributes, attitudes, and actions. Focusing on informal political discussion networks and their roles in shaping one's political preferences, the purpose of this dissertation is to uncover complex mutual interdependencies and the dynamic processes of which individuals' political attributes and political discussion networks simultaneously evolve over time. Motivated by a number of recent advancements in studies of dynamic co-evolution of one's attributes and social networks, the current study proposes and tests comprehensive theoretical accounts of social selection and social influence processes. First, longitudinal dynamics of social selections are examined in terms of demographic and political homophily, political interest and knowledge, availability and intimacy of dyadic relationships, and higher-order network endogenous effects. Second, possible mechanisms of normative and informational social influence and their relationships with dyadic differences of political interest and knowledge, with some graph-theoretical properties of political discussion networks, were examined. Using the Temporal Exponential Random Graph Models and the Generalized Estimating Equations, a series of whole network panel data from a number of large U.S Midwestern universities were used to test the proposed hypotheses. Findings suggest that political preference homophily is not likely to drive the structuring individuals' political discussion, but rather political discussion networks were largely driven by one's exogenous social relationships and network-endogenous processes. The impact of political preference homophily was generally limited, but individuals are more likely to form political discussion ties with those who are more interested in politics. Concerning the possible mechanisms of social network influence, none of the expected interaction effects were found although significant unconditional effects of an alter's political preferences on an ego's were observed. A series of supplementary analyses suggested that the other types of social ties -- close friends and time-spent together networks -- were indeed capable of inducing similarities in political preferences between an ego and alters without explicit political interactions. Moreover, the results suggested that, coupled with more "visible" attributes (smoking and happiness), an ego's highly interconnected, closure-like local network were more likely to amplify alters' influence on the ego, therefore suggesting that normative influence is likely within the social influence processes. Implications for the coevolution of social networks and one's attributes, and suggestions for future research are discussed. |
