How Facebook Figures Out Everyone You've Ever Met (gizmodo.com)

"I deleted Facebook after it recommended as People You May Know a man who was defense counsel on one of my cases. We had only communicated through my work email, which is not connected to my Facebook, which convinced me Facebook was scanning my work email," an attorney told Gizmodo. Kashmir Hill, a reporter at the news outlet, who recently documented how Facebook figured out a connection between her and a family member she did not know existed, shares several more instances others have reported and explains how Facebook gathers information. She reports: Behind the Facebook profile you've built for yourself is another one, a shadow profile, built from the inboxes and smartphones of other Facebook users. Contact information you've never given the network gets associated with your account, making it easier for Facebook to more completely map your social connections. Because shadow-profile connections happen inside Facebook's algorithmic black box, people can't see how deep the data-mining of their lives truly is, until an uncanny recommendation pops up. Facebook isn't scanning the work email of the attorney above. But it likely has her work email address on file, even if she never gave it to Facebook herself. If anyone who has the lawyer's address in their contacts has chosen to share it with Facebook, the company can link her to anyone else who has it, such as the defense counsel in one of her cases. Facebook will not confirm how it makes specific People You May Know connections, and a Facebook spokesperson suggested that there could be other plausible explanations for most of those examples -- "mutual friendships," or people being "in the same city/network." The spokesperson did say that of the stories on the list, the lawyer was the likeliest case for a shadow-profile connection. Handing over address books is one of the first steps Facebook asks people to take when they initially sign up, so that they can "Find Friends." The problem with all this, Hill writes, is that Facebook doesn't explicitly say the scale at which it would be using the contact information it gleans from a user's address book. Furthermore, most people are not aware that Facebook is using contact information taken from their phones for these purposes.

Comments

Re: LinkedIn Also.

[Anonymous Coward]

On the contrary, it is an excellent easy to game advertising platform, for psychopaths... The users are such soft targets. I mean, look what they elected for president! And it was done on a comparatively shoestring budget... It is both hilarious and tragic

Geolocation

[Albanach]

I'm expect that using the system tools to block access to the address book is probably sufficient on Android and iOS - so long as it's done before the app is ever launched.

What surprises me more is that people don't consider geolocation. Many many facebook users share their location with Facebook. It's then trivial for facebook to see that you are repeatedly in the same location at the same time as another person.

That lawyer might have met defense counsel at a couple of mediation hearings in a lawyer's office, then they went to the same court house at the same time every day for a week. It's easy to suppose they know each other.

Similarly for the sex worker who meets the same client at a handful of different hotels. Both their phones arrived at the hotel at the same time on the same days. Then they left together. Again, the connection is trivial.

At least with Google, you are paid for this data with better traffic reports and better directions. You can decide if that is worth it or not. With Facebook it seems you get nothing in return while they amass a huge amount of information you thought was private.

Re:Geolocation

[nine-times]

What surprises me more is that people don't consider geolocation. Many many facebook users share their location with Facebook. It's then trivial for facebook to see that you are repeatedly in the same location at the same time as another person.

I've actually been suspicious for a while that Facebook is doing something with geolocation.

I have a Facebook account. The main reason I have it because of friends and family who expect you to have it. I look at it sometimes, but almost never post anything. A couple of years ago, Facebook got pretty aggressive in sending notifications suggesting that I "friend" people that I might know-- not like I was looking for people that I might know, but they were actively sending me notifications. At first, it gave me a bunch of people that I did in fact know, and I friended some of them and it all seemed normal.

But then, within about a month, they got even more aggressive with the notifications, and a lot of the notifications were for people that I did not know. It seemed odd to me. Of the ones that I didn't know, some of them did seem a little familiar, like maybe I'd met them before. I was looking at the profile picture for one of those suggestions, and it clicked: It was someone who worked in the same building as I do. Not the same company, or on the same floor, but it was someone I'd seen in the elevator multiple times.

I looked through the other suggestions again, and realized some lived in the same apartment building. Over the next couple of weeks, I seemed to get a lot of suggestions to be friends with people who lived or worked in areas that I frequently visited. There was a girl who worked at a coffeeshop near my office, and a guy I sometimes saw walking around my neighborhood.

I spent a while trying to figure out how it would have made the connection, and the only thing I could think of was location. There were no Facebook friends in common, and no other connection I could find. I hadn't put my work or home address into Facebook. I'm pretty sure it had to be going off the GPS, noticing that I spent a lot of time in the same location they had, and made a connection that way. I'm still convinced that must be the explanation.

What's a bit disturbing to me is that I don't use the Facebook app much, and like I said, I almost never post anything. It's possible that the couple of things that I've posted were posted at home and at work, and it made the link based on that, but I'm still left wondering when Facebook is gathering location information. Does it gather information whenever you look at Facebook, whether you post or not? Does it gather location information from your phone, even when the Facebook app isn't open?

Re:Geolocation

[h4ck7h3p14n37]

Does it gather information whenever you look at Facebook, whether you post or not? Does it gather location information from your phone, even when the Facebook app isn't open?

Do you really have to ask? Of course the app is cyber stalking you!

If you have to use Facebook from your phone I would recommend using the website. It's still tracking you, but it won't be able to access the data on your phone. You should also consider turning off GPS. Do you really want someone to be able to easily determine your daily routines?

I hate sounding like a Luddite since I got into computers when I was a little kid, but technology has turned the Internet and our electronic devices into a pervasive surveillance system. The only way to resist is to not participate.

Shadow Profile

[XXongo]

If you read the article: https://gizmodo.com/how-facebo... Facebook is constructing a "shadow profile" of you, taken from other people sharing information.

Here are some of the cited links:
http://mashable.com/2013/06/26/facebook-shadow-profiles/
http://www.zdnet.com/article/anger-mounts-after-facebooks-shadow-profiles-leak-in-bug/
http://www.zdnet.com/article/firm-facebooks-shadow-profiles-are-frightening-dossiers-on-everyone/
https://splinternews.com/facebook-recommended-that-this-psychiatrists-patients-f-1793861472