Who Controls Your Facebook Feed

Every time you open Facebook, one of the world’s most influential, controversial, and misunderstood algorithms springs into action. It scans and collects everything posted in the past week by each of your friends, everyone you follow, each group you belong to, and every Facebook page you’ve liked. For the average Facebook user, that’s more than 1,500 posts. If you have several hundred friends, it could be as many as 10,000. Then, according to a closely guarded and constantly shifting formula, Facebook’s news feed algorithm ranks them all, in what it believes to be the precise order of how likely you are to find each post worthwhile. Most users will only ever see the top few hundred.

No one outside Facebook knows for sure how it does this, and no one inside the company will tell you. And yet the results of this automated ranking process shape the social lives and reading habits of more than 1 billion daily active users—one-fifth of the world’s adult population. The algorithm’s viral power has turned the media industry upside down, propelling startups like BuzzFeed and Vox to national prominence while 100-year-old newspapers wither and die. It fueled the stratospheric rise of billion-dollar companies like Zynga and LivingSocial—only to suck the helium from them a year or two later with a few adjustments to its code, leaving behind empty-pocketed investors and laid-off workers. Facebook’s news feed algorithm can be tweaked to make us happy or sad; it can expose us to new and challenging ideas or insulate us from ideological bubbles.

And yet, for all its power, Facebook’s news feed algorithm is surprisingly inelegant, maddeningly mercurial, and stubbornly opaque. It remains as likely as not to serve us posts we find trivial, irritating, misleading, or just plain boring. And Facebook knows it. Over the past several months, the social network has been running a test in which it shows some users the top post in their news feed alongside one other, lower-ranked post, asking them to pick the one they’d prefer to read. The result? The algorithm’s rankings correspond to the user’s preferences “sometimes,” Facebook acknowledges, declining to get more specific. When they don’t match up, the company says, that points to “an area for improvement.”

“Sometimes” isn’t the success rate you might expect for such a vaunted and feared bit of code. The news feed algorithm’s outsize influence has given rise to a strand of criticism that treats it as if it possessed a mind of its own—as if it were some runic form of intelligence, loosed on the world to pursue ends beyond the ken of human understanding. At a time when Facebook and other Silicon Valley giants increasingly filter our choices and guide our decisions through machine-learning software, when tech titans like Elon Musk and scientific laureates like Stephen Hawking are warning of the existential threat posed by A.I., the word itself—algorithm—has begun to take on an eerie affect. Algorithms, in the popular imagination, are mysterious, powerful entities that stand for all the ways technology and modernity both serve our every desire and threaten the values we hold dear.
Facebook’s news feed ranking team believes the change in its approach is paying off. “As we continue to improve news feed based on what people tell us, we are seeing that we’re getting better at ranking people’s news feeds; our ranking is getting closer to how people would rank stories in their feeds themselves,” says Scissors, the user experience researcher who helps to ovesee the feed quality panel.

There’s a potential downside, however, to giving users this sort of control: What if they’re mistaken, as humans often are, about what they really want to see? What if Facebook’s database of our online behaviors really did know us better, at least in some ways, than we knew ourselves? Could giving people the news feed they say they want actually make it less addictive than it was before?

Mosseri tells me he’s not particularly worried about that. The data so far, he explains, suggest that placing more weight on surveys and giving users more options have led to an increase in overall engagement and time spent on the site. While the two goals may seem to be in tension in the short term, “We find that qualitiative improvements to the news feed look like they correlate with long-term engagement.” That may be a happy coincidence if it continues to hold true. But if there’s one thing that Facebook has learned in 10 years of running the news feed, it’s that data never tell the full story, and the algorithm will never be perfect. What looks like it’s working today might be unmasked as a mistake tomorrow. And when it does, the humans who go to work every day in Menlo Park will read a bunch of spreadsheets, hold a bunch of meetings, ran a bunch of tests—and then change the algorithm once again.
A small team of engineers in Menlo Park. A panel of anonymous power users around the world. And, increasingly, you.
By Will Oremus