Great post by Gillian K. Hadfield on a recent paper in JAIR's AI & Society track on public opinion and online polarization.
Social media makes it look like the public is deeply divided. But what if most of the public just isn’t speaking? In a new paper with Atrisha S. just published in the Journal of Artificial Intelligence Research, we show that the polarization we observe online can emerge even when nobody’s opinions have changed. We call it rational silence. Most research on polarization assumes something is pushing people’s views apart: echo chambers, filter bubbles, algorithmic radicalization. Our model shows something different. We don’t change anyone’s opinions. We just let individuals weigh the costs and benefits of speaking up. When rhetoric heats up, two things squeeze moderates out. Allies speaking loudly substitute for your own voice, reducing your incentive to add to the chorus. And intense rhetoric from opponents shrinks the reward you get from expressing your view. Either way, moderates lose the reason to speak. The people who remain are those whose views are extreme enough that the reward from expression still outweighs the cost. It gets worse. We show that ideological media organizations, partisan outlets and political influencers, amplify the effect by signaling that the other side is more extreme than it really is. That makes speaking up feel even less worthwhile for moderates and pushes more of them into silence. Platform recommender systems, optimizing for engagement, then sort people into communities where the loudest voices dominate. Here’s what I worry about. Policymakers and legislators increasingly look to social media to gauge where the public stands. If expressed opinion is systematically skewed toward the extremes, our democratic institutions are navigating with a broken compass. And AI models trained on internet data inherit the same distortion, producing outputs that reflect who spoke up rather than what opinions people actually hold. For every company building AI products on top of that data, this is a problem. We identify practical interventions. Platform moderation that accounts for the intensity of the underlying opinion, not just the intensity of the rhetoric. And recommender strategies that prioritize participatory content over ideological content for users with strong views. One surprise from the model: blanket moderation that raises the cost of rhetoric for everyone can backfire, discouraging moderates more than extremists. The fix isn’t changing what people think. It’s changing who gets heard. https://lnkd.in/ekCnpq6d