Modeling Fake News in Social Networks with Deep Multi-Agent Reinforcement Learning
Authors: Christoph Aymanns, Matthias Weber, Co-Pierre Georg, Jakob Foerster
Keywords: deep multi-agent reinforcement learning, fake news, social networks, information aggregation
TL;DR: We model fake news on social networks using deep multi-agent reinforcement learning and propose interventions to curb the effectiveness of fake news in swaying public opinion. 
Abstract: We develop a practical and flexible computational model of fake news on social networks in which agents act according to learned best response functions. We achieve this by extending an information aggregation game to allow for fake news and by representing agents as recurrent deep Q-networks (DQN) trained by independent Q-learning. In the game, agents repeatedly guess whether a claim is true or false taking into account an informative private signal and observations of actions of their neighbors on the social network in the previous period. We incorporate fake news into the model by adding an adversarial agent, the attacker, that either provides biased private signals to or takes over a subset of agents. The attacker can follow either a hand-tuned or trained policy. Our model allows us to tackle questions that are analytically intractable in fully rational models, while ensuring that agents follow reasonable best response functions. Our results highlight the importance of awareness, privacy and social connectivity in curbing the adverse effects of fake news.