Jonathan Stray is a Senior Scientist at the Berkeley Center for Human-Compatible AI (CHAI), working on recommender systems — the algorithms that select and rank content across social media, news apps, streaming music and video, and online shopping. He studies how their operation affects well-being, polarization, and other things, and tries to design recommenders that are better for people and society. For a decade he taught the double masters in computer science and journalism at Columbia Journalism School (lectures online). He led the development of Workbench, a visual programming system for data journalism, and built Overview, an open-source document set analysis system for investigative journalists. For a while he was an editor at the Associated Press, and has also written for the New York Times, Foreign Policy, ProPublica, MIT Tech Review, and Wired. Before that, he did computer graphics R&D at Adobe Systems.