An anonymous reader quotes a report from 404 Media: X's algorithm learns what you hate and shows you more of it, according to a new study just published in the Proceedings of the National Academy of Sciences (PNAS). The paper, titled Value misalignment of X's feed algorithm is a reflection of value tensions in engagement, found that the site's algorithm prioritized engagement above all else when it generated a user's For You Page. It also showed that X serves more ragebait to people who say they are Democrats, although the exact reason for that is unclear. "In 2026 that's maybe not the most surprising headline ever," Ziv Epstein, a postdoctoral researcher at Stanford University, and co-author of the paper, told 404 Media. "So we actually dug in a little deeper to figure out why this is actually happening, and it turns out that X's feed algorithm, like a lot of these social media algorithms, is optimized for engagement [but] it turns out that not all types of engagement are considered equally." The researchers found that X's algorithm can push users toward content that conflicts with their stated values, especially when they reply to posts that anger or provoke them. Although replies accounted for just 6.8% of interactions, they appeared to carry disproportionate weight: "It's this feedback loop of outrage baiting. The algorithm learns that you get outraged and then continues to serve more content in that direction," said Epstein. It's unclear why X seems to serve ragebait to Democrats more often than Republicans. 404 Media speculates that it may be because there's more rightwing content on X overall or that Democrats tend to engage with posts they disagree with more often. "There might be some kind of differential effects on information diets there, or it might be something more psychological about how different you know partisan identities are triggering different kinds of actions and reactions, but ultimately I don't want to speculate too much," said Epstein. X's former product chief Nikita Bier confirmed that the site had been set to favor replies. "This is no longer true," Bier said in a post on X. "The largest contributor of seeing ragebait was the reply predictor and we were aware that angry replies were causing people to see more of that content. So last month, we gave the reply predictor a 15x boost if it's a friend's post -- and it reduced ragebait by [an] order of magnitude."

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