How algorithms (secretly) run the world

In this Monday, June 4, 2012, file photo, a girl looks at Facebook on her computer in Palo Alto, Calif. “Fake news,” which has gotten a lot of attention for its potential role in swaying the 2016 presidential election, has fascinated researchers for some time. Their studies have yielded tools that help track how “alternative facts” spread, and others that let you identify fake stories or block them altogether. Some of these are still baby steps in dealing with the phenomenon, but they’re part of a larger effort that now involves Facebook, Google and big media companies actively trying to tamp down the spread of fake stories. —AP Photo

WHEN you browse online for a new pair of shoes, pick a movie to stream on Netflix or apply for a car loan, an algorithm likely has its word to say on the outcome.

The complex mathematical formulas are playing a growing role in all walks of life: from detecting skin cancers to suggesting new Facebook friends, deciding who gets a job, how police resources are deployed, who gets insurance at what cost, or who is on a “no fly” list.