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If you have too few "friends" on Facebook, people might think you're a loser. Too many and people might think you're a social slut. Is there an optimal number?
First let me point out that any perceptions people have of your personal characteristics based on how connected you are in a social network may actually be valid. A study published Monday in PNAS [pdf] reveals that social connectivity is partially genetic. Researchers James Fowler, Christopher Dawes, and Nicholas Christakis compared data on 1,110 identical and fraternal twins from 142 schools and found heritability in "in-degree" (how many people call you a friend), "transitivity" (how many of your friends are friends with each other), and "centrality" (how easy it would be to play six degrees of Kevin Bacon using you in the role of Kevin Bacon). "Out-degree" (how many people you name as friends), however, is not significantly heritable.
The researchers also ran some computer simulations (using their "Attract and Introduce" model) and found that virtual people with heritable in-degree (how attractive you are as a friend) and connectivity (how often you introduce your friends) created network pattens that matched the real-life data.
The study doesn't say which heritable personality traits might contribute to popularity, but another paper coming out in the Journal of Personality and Social Psychology does. Psychologist Alexandra Burt tested the DNA of 200 male college students, put them in groups for the purpose of planning a party, and then had them rate each other's likability. She found that the most popular students were the most likely to bust the budget or suggest illegal stuff like drugs and hookers. They also tended to carry a variation of a serotonin-receptor gene associated with impulsivity and rule-breaking behavior. Everyone likes the bad boys.
Covering the PNAS paper, Richard Lawson wrote on Gawker, "The way the world works, you are either cool and have 600 Facebook friends, or you are worthless and only have 40." But is that true? Does 600 = cool?
In research published last year in the Journal of Computer-Mediated Communication (and covered in Psychology Today), college students viewed Facebook profiles that were identical except for the number of friends—either 102, 302, 502, 702, or 902—and rated the target's social attractiveness (without paying special attention to friend quantity). The number with the best results: 302. Appeal dropped off above and below that.
How can you have, as the authors write, "too much of a good thing?" They hypothesize that "Individuals with too many friends may appear to be focusing too much on Facebook, friending out of desperation rather than popularity, spending a great deal of time on their computers ostensibly trying to make connections in a computer-mediated environment where they feel more comfortable than in face-to-face social interaction."
So there you go. If you're looking for an excuse to start trimming nodes from your online network, besides getting a free Whopper or avoiding urgent updates that some guy you met once was super-poked by a Zombie flower, be a rule- and friendship-breaker and do it for your own popularity. Come on, would James Dean have 900 Facebook friends? Of course not. And he'd still be on Friendster, just cuz.
Jackson, M. (2009). Genetic influences on social network characteristics. Proceedings of the National Academy of Sciences, 106 (6), 1687-1688 DOI: 10.1073/pnas.0813169106
Burt, A. (2009). A mechanistic explanation of popularity: Genes, rule breaking, and evocative gene–environment correlations. Journal of Personality and Social Psychology, 96 (4), 783-794 DOI: 10.1037/a0013702
Tong, S., Van Der Heide, B., Langwell, L., & Walther, J. (2008). Too Much of a Good Thing? The Relationship Between Number of Friends and Interpersonal Impressions on Facebook Journal of Computer-Mediated Communication, 13 (3), 531-549 DOI: 10.1111/j.1083-6101.2008.00409.x
