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Why your friends list gets polluted over time

Best friends forever?
I’ve recently been doing some qualitative research into how people use social networks, and I’ve learned a great deal of interesting stuff through these interviews. Typically, I’m spending about an hour at a time having folks go through exercises like describing 2-3 items that represent them, drawing out their social network, talking about meeting new people, and a bunch of other random things.

While doing this, I’ve been paying attention to something that’s been bothering me over time as people friend me on Facebook:

Why does my friend list get so polluted over time with people I don’t know at all?

As a great rush of people in SF have gotten on Facebook, I’ve gotten regular friend requests – mostly legit, but some completely random strangers – and over time, I’ve collected a pretty large group. However, my group is much larger than the so-called Dunbar number, which estimates the largest group size that humans can have social relationships with. (It’s 150, by the way)

In fact, this entire issue of “real friends” versus “fake friends” has been an issue in social networks for a long time. First, with Fakesters on Friendster, then talk of “fake friends” on MySpace, and even certifications for folks on dating sites. In the past, it’s been said that Facebook actually reflects your “real life” friends because of all the geographical semi-private network stuff they do, but over time, I’ve found my own personal network saturated.

Friendships are complex
The first underpinning of this discussion is that friendship networks are actually very complex, and are poorly approximated by the “friends” versus “not friends” paradigm, or even the “friends”, “top friends”, and then “not friends” paradigm. In fact, you’ll see that a lot of social maps look like this:

This is my sister’s social map that she drew out for me, and is one of about half a dozen I’ve seen so far. What you’ll see is several overlapping networks based on geographical location (SF versus seattle), organizational affiliation (school/work/etc), sub-organizational affiliation (fraternity at school), versus strength of relationship.

And in fact, once you have this social map drawn out, one of the most interesting questions you can ask people is how they figure out in what situations they should:

  • call someone
  • text someone
  • e-mail someone
  • poke them
  • write on their wall
  • write them a message
  • meet them in person
  • etc

What you’ll find, in that discussion, is that there’s a steady progression of “commitment” that it takes to go from writing on a wall (the least burdensome thing) versus meeting them in person (the most burdensome thing). In fact, one of the really useful things that social networks provide that e-mail doesn’t is a range of expressiveness in your communication such that you can use it for more things than sending notes or data across the wire.

Where does adding a friend go into this?
Interestingly enough, if you ask people where “adding a friend” fits into the spectrum of interaction, where do they put it?

That’s right: They put it in the very beginning as the EASIEST and LEAST burdensome interaction they have with people. So in fact, if you don’t know someone at all, or you are just acquaintances with them, the first thing you do is add them to your friends.

And folks, that is not much of a filter at all ;-)

So what you’ll find is that as your social network evolves online, you’ll end up accumulating more and more acquaintances as a % of your total friends, until your friend list is by far mostly people you don’t know (or that you knew in the past), but that you don’t really care to see all their pictures and their app installs and all that stuff.

It’s very unclear how to come up to a solution for this – you certainly don’t want people to need to describe their social networks at the level I asked them to, yet there’s enough complexity and detail in your social relationships that you need to capture a lot of detail in order to fix the friends problem.

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