[nutmeg]

Another anecdotal-data-of-sample-size-one, my wife was at a bar and struck up a conversation with another person to whom she had no connections. After she left, Facebook suggested this person as a friend.

The other person may have searched for her on Facebook, causing her to be listed as a possible friend. Or perhaps Facebook uses location data to group people that are in the same location for an extended period of time.

It would be interesting if someone at Facebook could provide some insight into this.

[cylinder]

Why do people keep the Facebook app installed? I use it in the web browser and it works just fine, while sort of sandboxing it within Chrome.

[click170]

Especially after that incident where the Facebook app intentionally changed the email address of contacts in your phone to use Facebook.com email addresses instead of their real ones. All Facebook apps have been banned from all my devices since then.

[giancarlostoro]

Because my phone wont let me uninstall it [0] and it's not just on my specific phone, other manufacturers do the same. I also cannot uninstall Amazon or the 5 other completely useless apps it brings, Facebook Messenger and Instagram are ingrained into my phone which is annoying. I wish rooting and setting up a custom ROM wasn't a painful experience or I would do both, but I like getting updates, which rooting stops, and I'm not too sure a ROM supports updating properly.

[0]: https://www.reddit.com/r/androidapps/comments/3catb0/i_cant_...

[Qiasfah]

Have you tried disabling the apps instead of uninstalling them?

I've had good luck with this on stock roms when you can't uninstall the carrier's apps. Settings » Apps » All » Application Name » Disable

Technically the app is still there, but it can't be launched and doesn't appear in the list of apps.

[wernercd]

Which is why root is important...

Top 3 reasons: removing "crap", backing up crap and real adblocking.

[usefulcat]

Maybe they haven't heard of Tinfoil, a wrapper around the FB mobile site.

https://play.google.com/store/apps/details?id=com.danvelazco...

[ag_47]

Ditto. You can even get notifications from Chrome, and the facebook website supports it. Chat is by far the biggest hassle, but I'm willing to pay the price. I see the slightly degraded experience as a good incentive to not go on Facebook as often.

[untog]

Because "people" aren't even aware that this stuff can happen. I actually think it's far more likely that in this situation the other person did a search, but most people wouldn't even consider that a simple search could result in you ending up on a "People You May Know" list.

TL;DR: people don't know because they aren't savvy, and that isn't their fault. Those of us who do know should do a better job, but no, I have no ideas how either.

[superuser2]

On iOS you can simply not grant it contacts, microphone, or location access.

[krupan]

This should also be true for android as of version 6. I haven't tried installing the facebook app to make extra sure, but I get to choose with every other app I use.

[Spooky23]

I've observed usually around the release of creepy features, that they update the mobile website and fubar it in the process.

I think that the mobile site is the lowest priority interface.

[dionidium]

I actually tried this on iOS a few months ago. The experience was far worse -- felt slower, less responsive, harder to navigate -- so I re-installed the app.

[flying_kangaroo]

On the flip-side, (again, anecdotal sample-size-1) I've noticed a definite improvement in battery life after uninstalling the app, and I definitely don't needs any of Facebook's notifications to propagate through via the app.

[cylinder]

My Facebook experience is not very involved. I just scroll through the news feed, look at some photos/comments. Works fine for me, but if you are a heavier user, the app will of course be more fluid.

[lmm]

It performs a bit better. It can fit better on a small screen without the browser chrome. It handles loss of connection a lot better.

[overcast]

That's the opposite of my experience when I was using Facebook(a year ago). The app was awful, crashed regularly, and was much slower retrieving data. The mobile version was a much smoother experience.

[knodi123]

If so, that's recent. I uninstalled the app solely because the web version was much faster for me.

[lucasmullens]

And it's only getting better now with PWA features

[Kiro]

Notifications, chat bubbles etc.

[anysz]

+1 This happened to me at the supermarket.

Super cute cashier girl. No idea what her name is.

As I'm heading out I open up my news feed and what do you know? There she is in recommended friends. WTF

[heimatau]

This is a solid example, in relation to the OP comment. Since you didn't know her name. But...there is still a possibility that you had mutual friends and her face popped up. I used FB a lot and FB cycles many friends multiple times, in the hope that someone connects with you. I'm really good a remembering faces and well, this was what happened to me, numerous times. I might not knew the person in January but in July, I'd randomly meet them. FB showed me their photo probably 5 times in the process but it wasn't until the 5th time that I requested.

[anysz]

We had no mutual friends. I actually have 0 friends on Facebook. I use it as a media outlet.

All my recommended friends come from my iOS Contacts, by phone number. So the fact she popped up is absurd

[mgr86]

woah this almost seems like Facebooks version of Hot Single Girls Near you. Except they might actually be near you.

[astazangasta]

How is this possible even in principle? Location tracking might be one explanation - they certainly have access to the data - but it seems implausible for Facebook to be suggesting you friend every goddamn person you walk past. They couldn't have known you thought she was attractive, so what gives?

[PeCaN]

My guess:

Since anysz mentioned he has 0 friends, there will be no social graph recommendations. Thus less-confident recommendations will show up, including spending some minutes in the same location as someone. It could then consider other factors—opposite genders, relatively close in age, maybe similar interests.

[eunoia]

Healthy skepticism aside,

> They couldn't have known you thought she was attractive

Are you so sure? To me (no ML experience) that seems a somewhat solvable problem if you have a competency in ML and Facebook's data.

Just imagine if Tinder shared data back...

[astazangasta]

So, since people largely agree on who is attractive, does this mean FB would be recommended this poor lady to all the schlubby loners who wander through her checkout line? "The digital pimp, hard at work."

[firethief]

You probably don't use your real name for the FB account, do you? (Ruling out the "she saw your name on your moneycard and googled you on Facebook" hypothesis)

[heimatau]

Hmm. That's bizarre. Heck, innovation isn't stagnant. Maybe they did do this. Could become bad PR for FB, if proven.

[revscat]

Had the same thing happen to me after a date. We met on a dating site, agreed to meet for drinks. I never even knew her last name. The date didn't go well, so we ended it early. Afterwards, she showed up on my recommended friends list, and I assume I on hers.

Creepy.

[zghst]

I think FB does matching with phone number, if they have your presumed phone number in your contacts, it will link you in the graph

[renaudg]

Could you and the girl have shared the same IP address at some point (because of store Wi-Fi, or CGNAT with your cell carrier) ?

Disclaimer : I'm a former FB engineer but have no specific knowledge of this area. I suspect that IP addresses could be used as input for the PYMK feature though (in the absence of anything better, as you had 0 friends), as they are for security systems.

[lawyao]

Nothing to complain about :-)

[morganvachon]

A similar instance on my part: I started working at a new job last year, but didn't add that information to my Facebook account or any other online account (even LinkedIn, which I trust even less than FB). Within a week all of my new coworkers started showing up as suggested friends.

Now here's the fun part: My government job has a strict electronic device security policy, and employees are forbidden from carrying cellphones, smart watches, and any other connected devices into the building; I have to leave my phone in the car. So, how does Facebook know that I have new connections with these people? The only thing I can think of is that each of them looked me up on the site after meeting me. Another more insidious thought is that Facebook is using GPS location data to see where I go every morning and depart from every evening and is assuming that it's my new job (Google did this in the past when I had an Android phone and had Google Now enabled, it figured out on its own where my last new job was, but that was a documented "feature").

Either way, Facebook now knows where I work even though I deliberately chose not to tell them.

[zippergz]

> The only thing I can think of is that each of them looked me up on the site after meeting me.

No. One or two looked you up, and they're connected to all of the others. That's how this works.

[komali2]

I once tried out Tan-tan, China's version of Twitter. I was idly swiping away until I saw, on one girl, "you have crossed paths with her twice!" underneath which was a Baidu maps frame showing Balboa Park station.

Swiftly uninstalled.

[ArtDev]

Interesting. So it is technically possible.

[animex]

There are dating apps entirely based on this model.

[mikestew]

You hand the cashier a credit card, she thinks you're cute, too. Cashier reads name on credit card, wonders "if he's on Facebook", looks you up and there's your connection. Something something Occam's Razor.

[mmastrac]

If Facebook has access to nearby Bluetooth device MAC addresses and your MAC addresses, I'd argue that this is actually quite likely.

[mikestew]

I was about to ask why Bluetooth would come into play, but then realized that I replied to the wrong comment (the intent was to reply to the one about the "super cute cashier"). Though giving some thought, your way would work, too. Assuming that one can get the MAC address on a mobile device (never tried on either of the major platforms).

[NiekvdMaas]

This happened multiple times to me in the past as well. Most likely the other person searched for my name on FB causing FB to recommend the searcher as friend to me (LinkedIn uses the same technique). Location data sounds strange, that'd mean FB would constantly recommend other people sitting in the same restaurant etc.

[AndrewKemendo]

Playing devils advocate here - isn't that supposed to be helpful? As in, what an amazing capability to be able to do that.

[astazangasta]

How is it helpful to have a computer tell me who I should be friends with?

[recursive]

It's not. But it could be useful for a computer to tell you who it thinks you might already be friends with, so you can find them on facebook.

[AndrewKemendo]

It's not telling you. Telling you would be automatically making you friends.

It's a suggestion based on factors along a social graph.

If it's right, great! Saved you time from searching, or nudged you to create a stronger communications channel than you previously had (ostensibly).

If it's wrong, you just ignore it.

[astazangasta]

>If it's right, great! Saved you time from searching, or nudged you to create a stronger communications channel than you previously had

This is a tiny, tiny good I never wanted that I am receiving in exchange for a massive surveillance apparatus profiling my entire internet life.

[LoSboccacc]

it could also use 'same ip' data, apparently, so if they were using the bar wifi you'd get a friend suggestion, even if you never gave location access to facebook.

[polartx]

A friend of mine was having a discussion with a contractor working in his yard about something he was entirely unfamiliar with--natural gas powered grills. Having never researched the topic before, he was a little unnerved later to have Facebook serving him natural gas grill content ads. (still having not ever google'd them or anything)

[dhimes]

That is fucking creepy. Whoa.

[OhHeyItsE]

My guess: either common wifi networks or IP addresses.

[MildlySerious]

I can confirm that Facebook suggests people that have looked up your name.

I don't use FB on my phone, never have. Hence no location/IP/network data. I have not filled out where I work, but searched the place up once before.

A coworker who wanted to friend me and presumably searched for my name still gets suggested as possible friend a year after I quit the place. We have no possible mutual friends, I have never been on his profile, or searched the names of any of my coworkers.

[coldtea]

>The other person may have searched for her on Facebook, causing her to be listed as a possible friend. Or perhaps Facebook uses location data to group people that are in the same location for an extended period of time.

Probably the first -- since I, and millions of people, stay with hundreds of people we don't know for the same period of time and more (in bars, airports, workplaces, queues, concerts, shops, etc), and they still are not suggested to us.

[themagician]

The location data thing is something Google+ used to use to recommend friends, so I can't see why Facebook wouldn't.

[ben_jones]

People who I've searched for always appear as recommendations afterwards. My best guess is that this is a reverse of that, your wife was searched and so got the recommendation. I still don't like it though.

[overcast]

It's definitely related to searches. That other person was doing the classic Facebook background check.

[animex]

This was more than likely caused by the other person Facebook searching for her profile.