Race, politics, travel plans: things Facebook's algorithm can't get right

There's a whole class of information that Facebook thinks it knows about me and is willing to sell - the problem is their data isn't entirely accurate

Facebook knows everything about you. At least that's what we, and the advertisers it sells us to, are constantly told. But a peek behind its algorithmic curtains suggests what it does know might be wrong.

As any of its 1.65 billion users can tell you, Facebook is constantly "updating" its privacy settings, which is why I tool through all my settings every few weeks. I try to keep a lock on what strangers can learn about me on Facebook or have access to; not because I'm disinclined to participate in the platform, but because my family is uncomfortable with strangers having access to their personal lives, and that seems fair.