In their study, Mozilla experts recruited volunteers who use a custom browser extension that adds a “Stop suggesting” button to their YouTube videos.

Details of the study

• Users were randomly assigned to a group, and each time they clicked the button, YouTube received different signals – “I don’t like”, “I’m not interested”, “Don’t recommend this channel”, “Remove from history”.
• A control group was also created from users who did not receive feedback on YouTube.
• Using data collected from 500 million suggested videos, the researchers created more than 44,000 video pairs, one that was rejected by a user and then one recommended by the service.
• The researchers then evaluated these pairs to see if the suggestion was similar to a video the user had previously rejected.
• As the comparison with the control group shows, Sending “Dislike” and “Not interested” signals is practically ineffective and does not block unwanted suggestions from YouTube. Only 12% and 11% of unsolicited suggestions were eliminated.
• buttons “Don’t recommend channel” and “Delete from history” turned out to be slightly more effective — Blocked 43% and 29% of spam redirects.

Researchers conclude that the tools YouTube offers are not enough to get rid of unwanted content.

YouTube should respect user feedback as meaningful signals about how users want to spend their time on the platform.
– write researchers.

YouTube is responding

The video hosting company has already responded to the allegations. YouTube representative Elena Hernandez told reporters of The Verge: this behavior of the platform is intentional. First, researchers Mozilla misunderstands the essence and special functions of research buttons. Second, YouTube doesn’t try to cut out all content on a particular topic.

It is important that our controls do not filter out all topics or viewpoints, as this can have negative consequences for the audience, such as creating echo chambers. We welcome academic research on our platform, so we recently expanded access to the Data API through the YouTube Research Programme. But Mozilla’s report doesn’t take into account how our systems actually work.
– says Hernandez.

Mozilla’s definition of similar content doesn’t take into account how YouTube’s recommendation system works, he said.

• The “I’m not interested” feature only deletes a specific video, not the entire topic.
• The “Don’t recommend this channel” button blocks future suggestions from a specific channel.

He explains that in such cases, YouTube does not intend to completely stop recommending any content related to a particular topic, opinion or speaker.