Facebook Figured Out My Family Secrets, And It Won't Tell Me How (gizmodo.com)
Kashmir Hill, reporting for Gizmodo: Rebecca Porter and I were strangers, as far as I knew. Facebook, however, thought we might be connected. Her name popped up this summer on my list of "People You May Know," the social network's roster of potential new online friends for me. [...] She showed up on the list after about a month: an older woman, living in Ohio, with whom I had no Facebook friends in common. I did not recognize her, but her last name was familiar. My biological grandfather is a man I've never met, with the last name Porter, who abandoned my father when he was a baby. My father was adopted by a man whose last name was Hill, and he didn't find out about his biological father until adulthood. The Porter family lived in Ohio. Growing up half a country away, in Florida, I'd known these blood relatives were out there, but there was no reason to think I would ever meet them. A few years ago, my father eventually did meet his biological father, along with two uncles and an aunt, when they sought him out during a trip back to Ohio for his mother's funeral. None of them use Facebook. I sent the woman a Facebook message explaining the situation and asking if she was related to my biological grandfather. "Yes," she wrote back. Rebecca Porter, we discovered, is my great aunt, by marriage. She is married to my biological grandfather's brother; she met him 35 years ago, the year after I was born. Facebook knew my family tree better than I did "I didn't know about you," she told me, when we talked by phone. "I don't understand how Facebook made the connection." How Facebook had linked us remained hard to fathom. My father had met her husband in person that one time, after my grandmother's funeral. They exchanged emails, and my father had his number in his phone. But neither of them uses Facebook. Nor do the other people between me and Rebecca Porter on the family tree.
Usually I hate being Anon on here, but this one is a bit to important to not mention.
TL:DR my late step father used to pimp me out to a pedophile bicker friend of his. Happened when I was about 11 to 13. During that time I ended up having to... well be kind of shield for my younger siblings too. Fast forward until I'm about 19 and my step father dies from heart problems from the meth the aforementioned mentioned biker was selling him. No one in my immediately family was using Facebook at the time, but all of a sudden we start getting hangup calls from some number we don't know. We eventually found out one our aunts had been putting all of these family photos up on Facebook and tagged us all in them and given that she's an idiot about security.
Now, my story ended better than it could and the police were actually able to find my abuser since he already had some warrents on him as is. But non the less, the damage had already been done to the security and piece of my entire family.
Facebook keeps showing me a person I might know and the only, ONLY, place I have ever seen the name before is in my Ancestry DNA match list. Never emailed. No common friends. We don't have a common ancestor in our trees yet and are about 5th cousins. The person lives in a different country, though I have visited the city and checked into places on FB.
I had some weirdness with Linkedin when it started sending me adverts and articles relating to living with someone with terminal cancer. Turns out one of my parents cats had colon cancer and they didn't want to tell me. So I would guess that the algorithms use a kind of diffusion process. Every person has their own unique ID number, then all bits of information about them get linked to that ID number. Each person also had links to other people. Then deductive logic can be applied. If someone is a skydiver, then all those links can be updated to have "knows someone who is a skydiver". Maybe this gets weighted by the number of people they know or how many links it takes.
Other time, I looked up something like "protecting property from grizzly bears" while renting an apartment downtown. Then I started receiving catalogs for bear traps, camo gear and hunting rifles.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads