Thesis: Social interactions are in the core of economic activities. Their treatment in Economies is however often limited to a focus on the market (Manski, 2000). The role social interactions themselves play for the behavior of agents as well as the formation of their attitudes is often neglected. This is despite the fact that already early contributions in economic literature have identified them as important determinants for the decision making of economic agents as for example Sherif (I936), Hyman (1942), Asch (1951 ), Jahoda (I 959) or Merton (1968). ln consumer research, a field on the intersection between Economies, Sociology and Psychology, on the other hand social interactions (social influences) are considered to be the" … most pervasive determinants [ … ] of individual 's behaviour. .. " (Bumkrant and Cousineau, 1975). The thesis at hand bridges the gap between social interactions and their influence on agents expectation formation and behavior.