"At one point during the 2016 presidential election campaign, I watched a bunch of videos of Donald Trump rallies on YouTube. I was writing an article about his appeal to his voter base and wanted to confirm a few quotations.
Soon I noticed something peculiar. YouTube started to recommend and â€śautoplayâ€ť videos for me that featured white supremacist rants, Holocaust denials and other disturbing content.
Since I was not in the habit of watching extreme right-wing fare on YouTube, I was curious whether this was an exclusively right-wing phenomenon. So I created another YouTube account and started watching videos of Hillary Clinton and Bernie Sanders, letting YouTubeâ€™s recommender algorithm take me wherever it would.
Before long, I was being directed to videos of a leftish conspiratorial cast, including arguments about the existence of secret government agencies and allegations that the United States government was behind the attacks of Sept. 11. As with the Trump videos, YouTube was recommending content that was more and more extreme than the mainstream political fare I had started with.
Intrigued, I experimented with nonpolitical topics. The same basic pattern emerged. Videos about vegetarianism led to videos about veganism. Videos about jogging led to videos about running ultramarathons. . . . The Wall Street Journal conducted an investigation of YouTube content with the help of Mr. Chaslot. It found that YouTube often â€śfed far-right or far-left videos to users who watched relatively mainstream news sources,â€ť and that such extremist tendencies were evident with a wide variety of material. If you searched for information on the flu vaccine, you were recommended anti-vaccination conspiracy videos."