Detecting Social Bots on Facebook in an Information Veracity Context

Santia, Giovanni C.; Mujib, Munif Ishad; Williams, Jake Ryland

Misleading information is nothing new, yet its impacts seem only to grow. We investigate this phenomenon in the context of social bots. Social bots are software agents that mimic hu- mans. They are intended to interact with humans while sup- porting specific agendas. This work explores the effect of so- cial bots on the spread of misinformation on Facebook dur- ing the Fall of 2016 and prototypes a tool for their detec- tion. Using a dataset of about two million user comments dis- cussing the posts of public pages for nine verified news out- lets, we first annotate a large dataset for social bots. We then develop and evaluate commercially implementable bot detec- tion software for public pages with an overall F1 score of 0.71. Applying this software, we found only a small percent- age (0.06%) of the commenting user population to be social bots. However, their activity was extremely disproportionate, producing comments at a rate more than fifty times higher (3.5%). Finally, we observe that one might commonly en- counter social bot comments at a rate of about one in ten on mainstream outlet and reliable content news posts. In light of these findings and to support page owners and their communi- ties we release prototype code and software to help moderate social bots on Facebook.