TY - THES A1 - Luzsa, Robert T1 - A Psychological and Empirical Investigation of the Online Echo Chamber Phenomenon N2 - In the public debate it is often assumed that communication in so-called “Echo Chambers” - online structures in which like-minded people share mostly messages that confirm their mutual, shared attitudes - can lead to negative outcomes such as increased societal polarization between groups holding opposing beliefs. This thesis aimed to examine this assumption from a psychological perspective and substantiate it empirically. First, based on existing research and psychological theories, a working definition of Echo Chambers was formulated, that highlights two key factors: Selective Exposure to attitudinally congruent messages and communication in homogeneous networks. Then, three studies were conducted to test links between these factors and two individual-level outcomes that are associated to subjects’ actual behavior: Their False Consensus, that is, how strongly subjects perceive the public in agreement with their own attitudes, and their Intergroup Bias, which reflects to which degree subjects’ identify as members of an in-group that is in conflict with negatively perceived out-groups. The studies employed questionnaire-based, experimental, as well as real-word data driven approaches. Overall, they confirm that exposure to Echo Chamber-like online structures can indeed lead to a more favorably distorted perception of public opinions and to more signs of Intergroup Bias in subjects’ communicational style. Thus, the thesis provides first psychologically founded empirical evidence for effects of online Echo Chamber exposure on behavior-related individual-level outcomes. The results can serve as a basis for further research as well as for the discussion of possible strategies to counter negative effects of online Echo Chambers. KW - False Consensus KW - Echo Chamber KW - Psychology KW - Falscher Konsensus-Effekt KW - Psychologie Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:739-opus4-7419 ER -