Will Oremus – 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 in 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.”
There is this kind of time travel experience we’ve all had now and then; when hearing a certain song brings back a flood of memories from our past. Emotional associations to the soundtrack of our lives do have a habit of letting some memories out for some fresh air; and when they do we’re momentarily caught up in this swirl of memories released from stasis.