Are Biases Contagious? The Influence of Communication on Motivated Beliefs

Abstract

This paper examines the potential reinforcement of motivated beliefs when two individuals with identical biases communicate. We propose a controlled online experiment that allows us to manipulate belief biases and the communication environment. We find that communication, even among like-minded individuals, diminishes motivated beliefs if it takes place in a communication environment without previously declared external opinions. In the presence of external plural opinions, however, communication does not reduce but rather aggravates motivated beliefs. Our results indicate a potential drawback of the plurality of opinions – it may create communication environments wherein motivated beliefs not only persist but may also become contagious within social networks.

Keywords: Belief bias, Social interaction, Motivated beliefs

JEL Classification: C91, C92, D83