Studies suggest that democracy functions best when voters have access to good information from diverse sources. A well-informed electorate is more likely to take an active interest in politics and hold politicians accountable. However, this ideal is undermined by “homophily” – the tendency for people to associate with those who share opinions similar to their own.
A recent study co-authored by economics professor Yosh Halberstam has documented how homophily influences political communications on Twitter. The authors analyzed more than 500,000 posts among 2.2 million politically active Twitter users during the 2012 American elections, and found that both conservatives and liberals were exposed to a disproportionate amount of like-minded information, creating a kind of echo chamber. Moreover, like-minded tweets reached each group more quickly than tweets holding an opposing position.