Troll Farms and Voter Disinformation

Abstract

Political agents often attempt to influence elections through troll farms – organisations that flood social media platforms with messages emulating genuine information. We model the behaviour of a troll farm that faces a heterogeneous electorate of partially informed voters, and aims to achieve a desired political outcome by targeting each type of voter with a specific distribution of messages. We show that such tactics are more effective when voters are otherwise well-informed. Consequently, societies with high-quality media are more vulnerable to electoral manipulation, and counteracting troll farms may require promotion of informative but non-expert opinions. At the same time, increased polarisation, as well as deviations from Bayesian rationality, can reduce the negative effect of troll farms and restore efficiency of electoral outcomes.

Keywords: social media, fake news, elections, polarisation, bounded rationality.

JEL Classification: D72, D83, D91