Characterizing Social Spambots by their Human Traits

Social spambots, an emerging class of spammers attempting to emulate people, are difficult for both human annotators and classic bot detection techniques to reliably distinguish from genuine accounts. We examine this human emulation through studying the human characteristics (personality, gender, age, emotions) exhibited by social spambots’ language, hypothesizing the values for these attributes will be unhuman-like (e.g. unusually high or low). We found our hypothesis mostly disconfirmed — individually, social bots exhibit very human-like attributes. However, a striking pattern emerged when consider the full distributions of these estimated human attributes: social bots were extremely similar and average in their expressed personality, demographics, and emotion (in contrast with traditional bots which we found to exhibit more variance and extreme values than genuine accounts). We thus consider how well social bots can be identified only using the 17 variables of these human attributes and ended up with a new state of the art in social spambot detection (e.g. F1 = .946). Further, simulating the situation of not knowing the bots a priori, we found that even an unsupervised clustering using the same 17 attributes could yield nearly as accurate of social bot identification (F1 = 0.925).