
Ask HN: How does FB's friend suggestion mechanism work? - bendavis381
A recent Reddit thread [1] suggests that FB is able to track location even without the installation of any of their apps. Is this via  tracking pixel or through a deal with Samsung&#x2F;Google?<p>[1] https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;privacy&#x2F;comments&#x2F;9z1205&#x2F;facebook_suggested_that_i_friend_a_person_that_i&#x2F;?st=JORDJ5U5&amp;sh=ef5fa5aa
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askafriend
My guess? Super easy.

You go to Facebook.com from mobile web.

Your friend or an acquaintance at a party does too.

Both of you are on the same wifi network or a very similar region - maybe one
that you visit often or one that you're not normally at (both are interesting
for different reasons). You can easily get that from IP or other network
characteristics/cookies. Facebook also has your friend graph so they can tell
whether you're connected in some way to some Nth degree.

That's all it takes.

It's probably not some fancy machine learning or AI (though I'm sure that's
sprinkled in somewhere to get a confidence level). It's also probably not some
evil scheme to trick you into sharing your location.

The sheer scale of the network alone is enough for even simple methods to be
highly effective and I think that's the crux of what people underestimate and
instead gravitate towards conspiracy theories.

