Since 2010, University of Colorado Denver doctoral student Christopher Sibona has researched Facebook via studies focusing on unfriending -- including the phenomenon of unfriending harming actual friendships. As for his latest two studies, they include a look at unfriending behavior that lists the sixteen kinds of people most likely to be unfriended.
Look below to count down all sixteen, supplemented by photos and very unscientific examples of unfriending targets who fit in each category.
Number 16: Friend through Parent
Example: Your widowed mom's elderly suitor, who's under the illusion that he's still up-to-date. He convinces you to accept his friend invite, then starts bombarding you with links to the Love Boat fan club. Number 15: Neighbor
Example: The guy next door who watches your every move. You think friending him will make him seem less creepy. Instead, you discover he's now spying on you via computer as well as in real life. Number 14: Friend through Child
Example: The irritating mom of the irritating child in your daughter's playgroup who thought she could improve her kid's social standing by cozying up to you, and you were too polite to say "no." You should have. Continue to keep counting down the top sixteen kinds of Facebook friends most likely to get unfriended. Number 13: Graduate school
Example: The obnoxious guy who insisted on staying in touch after school because you could help each other network. Except you'd never want to be in any network with someone like him. Number 12: Friend through Spouse
Example: The woman who your wife thinks is incredibly funny -- except she spends all her online time posting things that were out of date ages ago. Or do you still care how awkward Mariah Carey was on American Idol? Number 11: Grade school
Example: The bully who made third grade a living hell surfaces years later, and you friend him thinking that maybe he's changed. Think again. Continue to keep counting down the top sixteen kinds of Facebook friends most likely to get unfriended. Number 10: Church
Example: The guy who's so insecure about his faith that he shares about it every twenty minutes, day and night. Number 9: Family member
Example: Your psychotic aunt, whose daughter convinced her that getting on Facebook would open up a whole new world for her. Too bad she hates it even more than the one she's actually in. Number 8: Internet
Example: The person you're pretty sure you know -- until you begin wondering if it's actually a person at all. Continue to keep counting down the top sixteen kinds of Facebook friends most likely to get unfriended. Number 7: Romantic partner
Example: The person you broke up with two years ago. You pledged to stay in touch to prove how adult you both are. Too bad being adult can be so exhausting after a while. Number 6: College
Example: The roommate you friended as a way of cementing a bond that never really existed -- and now, every time you see her name, you can't remember why you resisted the urge to strangle her in her sleep. Number 5: Common interest friend
Example: The raging asshole you keep on your bowling team because of his 212-pins-per-game average. But when the alley's closed, all that's left is the rage. Continue to keep counting down the top sixteen kinds of Facebook friends most likely to get unfriended. Number 4: Work
Example: The cubicle-mate who talks too loudly, invades your space on a regular basis and thinks you're real pals since you haven't reported him to HR. Yet. Number 3: Friend of a friend
Example: The aggressively annoying mouth-breather your buddy brings along to everything you do together -- and who'll get unfriended himself if it keeps happening. Number 2: Other
Example: Your best friend as a sophomore. The one you were sure was a soul mate -- until that day when you suddenly realized her head was emptier than the vastness of space. And now? She thinks Grumpy Cat is the funniest thing ever.
And now, for some actual science, here are Christopher Sibona's two latest studies.
If you like this story, consider signing up for our email newsletters.
SHOW ME HOW
You have successfully signed up for your selected newsletter(s) - please keep an eye on your mailbox, we're movin' in!
Send your story tips to the author, Michael Roberts.
More from our Tech archive circa October 2010: "Unfriending: Facebook study shows that posting unimportant stuff too often drives users up wall."