@article{2026:schweiger:social_inf,
title = {Social influence on social media. How majority and in-/outgroup opinions on personal newsfeeds impact opinion formation  on new issues},
year = {2026},
note = {Social media platforms play a central role in shaping public opinion
on political and societal issues. Users are constantly exposed to a
mix of algorithmically and socially filtered content, which can
influence how they perceive new topics and form attitudes. Drawing on
theories of heuristic information processing, social impact, and
social identity, an experimental study explored the impact of opinions
in a social media newsfeed on users’ selective attention,
evaluation, and opinion formation. A 2x2 design with N = 197
participants, integrating forced and selective exposure elements,
confronted subjects with a novel (fictitious) issue and a feed of six
related opinion posts. Two factors were analyzed: (1) whether posts
– in favor or against the issue – came from voices that
participants identified as ingroup versus outgroup, and (2) whether
the pro or con posts were in the majority versus minority. Results
show that posts from ingroup voices do not receive more attention than
outgroup posts but are perceived as more credible in general and are
more persuasive under certain conditions: When ingroup posts are in
the majority and when users are low-involved. The persuasive effect
also occurs when the ingroup is hardly related to the issue under
discussion. This underscores that no impermeable filter bubbles are
needed to influence user opinions on social media. According to the
results, persuasion takes place on social media when individuals are
predominantly confronted with the opinions of people with whom they
feel close and connected–regardless of whether this connection is
topic-specific or not.},
journal = {SCM Studies in Communication and Media},
pages = {253--280},
author = {Schweiger, Wolfgang},
volume = {15},
number = {2}
}