Evaluating Echo Chambers, Rabbit Holes, and Radicalization Pathways on YouTube

To what extent does the YouTube recommendation algorithm push users into echo chambers, rabbit holes, or radicalization pathways? Using a novel method to estimate the ideology of YouTube videos and an original audit design, we demonstrate that YouTube users are in mild ideological echo chambers, but this is primarily driven by user behavior. We also demonstrate that the recommendation algorithm prioritizes content that is similar to what the user is currently watching, producing content rabbit holes. However, we do not find evidence of radicalization pathways where users are driven into increasingly extreme content rabbit holes. Instead, we find that YouTube pushes all users, regardless of ideology, toward moderately conservative content and an increasingly narrow range of ideological content the longer they follow YouTube’s recommendations.