The relationship between the topology of a network and specific types of dynamics unfolding in networks constitutes a subject of substantial interest. One type of dynamics that has attracted increasing attention because of its several potential implications is opinion formation. A phenomenon of particular importance, known to take place in opinion formation, is echo chambers’ appearance. In the present work, we approach this phenomenon, while emphasizing the influence of contrarian opinions in a multi-opinion scenario. To define the contrarian opinion, we considered the underdog effect, which is the eventual tendency of people to support the less popular option. We also considered an adaptation of the Sznajd dynamics with the possibility of friendship rewiring, performed on several network models. We analyze the relationship between topology and opinion dynamics by considering two measurements: opinion diversity and network modularity. Two specific situations have been addressed: (i) the agents can reconnect only with others sharing the same opinion; and (ii) same as in the previous case, but with the agents reconnecting only within a limited neighborhood. This choice can be justified because, in general, friendship is a transitive property along with subsequent neighborhoods (e.g., two friends of a person tend to know each other). As the main results, we found that the underdog effect, if strong enough, can balance the agents’ opinions. On the other hand, this effect decreases the possibilities of echo chamber formation. We also found that the restricted reconnection case reduced the chances of echo chamber formation and led to smaller echo chambers.

网络拓扑结构与网络中展开的特定类型的动态之间的关系构成了一个非常有趣的主题。由于其多种潜在影响而引起越来越多关注的一种动态是意见形成。众所周知，在意见形成过程中会发生一个特别重要的现象，就是回声室的出现。在目前的工作中，我们处理这种现象，同时强调在多意见情景中逆向意见的影响。为了定义逆势观点，我们考虑了失败者效果，这是人们支持不太受欢迎的选项的最终趋势。我们还考虑了对 Sznajd 动力学的适应，并在几个网络模型上执行了友谊重新布线的可能性。我们通过考虑两个度量来分析拓扑和意见动态之间的关系：意见多样性和网络模块化。已经解决了两种特定情况：(i) 代理只能与拥有相同意见的其他人重新连接；(ii) 与前一种情况相同，但代理仅在有限的邻域内重新连接。这种选择是合理的，因为一般来说，友谊是与后续邻里一起的可传递属性（例如，一个人的两个朋友往往相互认识）。作为主要结果，我们发现如果弱者效应足够强，可以平衡代理人的意见。另一方面，这种效应降低了回声室形成的可能性。我们还发现，受限重连情况降低了回声室形成的机会，并导致回声室更小。