Big Tech monopolies are in the news this week. The Department of Justice sued Google over how it maintains its search dominance, and its search dominance is the key to its business model, which is that it makes 80% of its revenue from digital advertising. Facebook makes 99% of its revenue from advertising. The profitability of targeted ads is also a big reason why tech companies are constantly collecting so much data about us. And there’s a multibillion-dollar ad tech industry that exists because all of this makes so much money. But what if these ads didn’t work all that well? Molly Wood speaks with Tim Hwang, a former public policy exec at Google, where he worked on artificial intelligence and machine learning. He’s the author of the new book “Subprime Attention Crisis.”