This paper investigates the role of social bots in political propaganda on Twitter, focusing on the discourse surrounding migration from North Africa to Italy. Using an entropy-based null model to filter out random noise, the study reveals that bots play a central role in amplifying significant content. Key findings include the disproportionate number of bots among the followers of influential accounts ('hubs') and the existence of 'bot squads' – groups of bots that follow and retweet the same set of hubs, likely to increase the visibility of their messages. This coordinated bot activity is particularly evident among right-wing political accounts.

Guido Caldarelli, Rocco De Nicola, Fabio Del Vigna, Marinella Petrocchi, Fabio Saracco