Polarization caused by social media is seen by many as an important societal problem, which also overlaps with AI alignment (since social media recommendations come from ML algorithms). I have personally begun directing some of my research to recommender alignment, which has gotten me curious about the extent to which polarization is actually driven by social media. This blog post is the first in a series that summarizes my current take-aways. I’ll start (in this post) by looking at aggregate trends in polarization, then connect them with micro-level data on Facebook feeds in later posts.
I started out feeling that most polarization probably comes from social media. As I read more, my views have shifted: I think there’s pretty good evidence that other sources, including cable news, have historically driven a lot of polarization (see DellaVigna and Kaplan (2006) and Martin and Yurukoglu (2017)), and that we would be highly polarized even without social media. In addition, most readers of this post (and myself) are “extremely online”, and probably intuitively overestimate the impact of social media on a typical American. However, it is possible that social media has further accelerated polarization to an important degree, but the data are too noisy to provide strong evidence either way.Read more