90

Samuel C. Woolley

across

suspicious Twitter bot

These ﬁndings were backed up by several other prominent studies that both
preceded this work and have vindicated it since. Metaxas and Mustafaraj
(2012) discussed ﬁndings in Science illuminating a similar distribution of
inﬂuence
accounts used to defame
a Massachusetts Senate candidate in 2010. Kramer, Guillory, and Hancock
(2015), in the Proceedings of the National Academy of Sciences of the United
States of America (PNAS),
found that exposure to Twitter bots with
oppositional views increased political polarization among participants in an
experimental study. Woolley and Howard (2018), in a book of country-speciﬁc
case studies entitled Computational Propaganda, argued that bots are often
used during events around the world to spread and bolster misinformative and
disinformative stories online.
Social_Media_and_Democracy