Amsterdam Institute for Social Science Research, University of Amsterdam, Amsterdam, The Netherlands.
Complex Systems Group, Physical Resource Theory, Chalmers University of Technology, Gothenburg, Sweden.
PLoS One. 2021 Oct 11;16(10):e0258259. doi: 10.1371/journal.pone.0258259. eCollection 2021.
Rising political polarization in recent decades has hampered and gridlocked policymaking, as well as weakened trust in democratic institutions. These developments have been linked to the idea that new media technology fosters extreme views and political conflict by facilitating self-segregation into "echo chambers" where opinions are isolated and reinforced. This opinion-centered picture has recently been challenged by an emerging political science literature on "affective polarization", which suggests that current polarization is better understood as driven by partisanship emerging as a strong social identity. Through this lens, politics has become a question of competing social groups rather than differences in policy position. Contrary to the opinion-centered view, this identity-centered perspective has not been subject to dynamical formal modeling, which generally permits hypotheses about micro-level explanations for macro-level phenomena to be systematically tested and explored. We here propose a formal model that links new information technology to affective polarization via social psychological mechanisms of social identity. Our results suggest that new information technology catalyzes affective polarization by lowering search and interaction costs, which shifts the balance between centrifugal and centripetal forces of social identity. We find that the macro-dynamics of social identity is characterized by two stable regimes on the societal level: one fluid regime, in which identities are weak and social connections heterogeneous, and one solid regime in which identities are strong and groups homogeneous. We also find evidence of hysteresis, meaning that a transition into a fragmented state is not readily reversed by again increasing those costs. This suggests that, due to systemic feedback effects, if polarization passes certain tipping points, we may experience run-away political polarization that is highly difficult to reverse.
近几十年来，政治两极分化的加剧阻碍了政策制定的进程，并导致了僵局，同时也削弱了人们对民主制度的信任。这些发展与一个观点有关，即新媒体技术通过促进自我隔离到“回音室”中，从而助长了极端观点和政治冲突，在这些“回音室”中，观点是孤立和强化的。最近，关于“情感极化”的新兴政治学文献对这种以意见为中心的观点提出了挑战，该文献表明，当前的极化现象更好地理解为是由党派关系作为一种强烈的社会认同而出现所驱动的。通过这种视角，政治问题变成了竞争的社会群体问题，而不是政策立场的差异问题。与以意见为中心的观点相反，这种以身份为中心的观点尚未受到动态形式建模的检验，而动态形式建模通常允许对宏观现象的微观层面解释进行系统的测试和探索。在这里，我们提出了一个正式模型，该模型通过社会认同的社会心理机制将新信息技术与情感极化联系起来。我们的研究结果表明，新信息技术通过降低搜索和交互成本来促进情感极化，从而改变了社会认同的离心力和向心力之间的平衡。我们发现，社会认同的宏观动态在社会层面上有两个稳定的状态：一个是流动的状态，在这个状态中，身份较弱，社会关系多样化；另一个是坚固的状态，在这个状态中，身份较强，群体同质化。我们还发现了滞后的证据，这意味着通过再次增加这些成本，向碎片化状态的转变并不容易逆转。这表明，由于系统的反馈效应，如果极化现象超过了某些临界点，我们可能会经历难以逆转的失控的政治极化。
