Políticos y periodistas: un bucle endogámico en los medios sociales: Dominios compartidos en Twitter por diputados y periodistas españoles

This paper presents a study on how social media is used in political communication, specifically on how Twitter is used by politicians and journalists in Spain. Through a tool created ad hoc to monitor digital trace data, the authors observe - thanks to machine learning techniques - the hyperlinks that were shared both by the Spanish representatives in the XII National Congress and the main Spanish journalists from June 2018 to May 2019. The results reveal an endogenous relationship between journalists and politicians. The interaction between these two groups is produced in and around the main Spanish media, resulting in an inner flux of information shared by both groups within a self-referential bubble, thus producing an echo chamber effect and missing the enormous possibilities of knowledge expansion provided by social media through the accession to hypertext.