Diachronic political content analysis: a comparative study of topics and sentiments in Echo Chambers and beyond

Over the past decade, social media platforms have emerged as significant arenas for political discourse and agenda-setting. Among these platforms, Reddit stands out as a prominent site where users actively engage in discussions on controversial topics, often becoming polarized through interactions with like-minded individuals. In this paper, we delve into the realm of political leanings, seeking to understand the predominant topics of interest within echo chambers and whether they diverge from those of unpolarized users. Our primary objective is to ascertain whether echo chambers are characterized by distinct themes discussed therein. Furthermore, we employ cross-sentiment analysis to investigate potential differences in how these themes are perceived across different groups.