Image courtesy of Jennifer Daniel
How does Facebook know who your friends are? There’s still a lot of confusion and misinformation about what Facebook’s doing when it “finds” your friends. Alas, Facebook’s actual process isn’t actually that sneaky or malicious. In fact, it involves this pretty complex academic field called, network science.
In a nutshell, whenever you sign up for a Facebook account, Facebook asks permission to look at your e-mail contacts if you’re on a computer, or your phone contacts if you’re on a smartphone. When you grant the site permission, it searches your contacts for users already on the network, and it searches other users’ uploaded contacts for you. That gives it a very primitive outline of your social circles: who you know, but not how you know them or how well.
To refine that map, Facebook asks you more questions about yourself: where you went to school, when you were born, what city you live in. Each field in your Facebook profile and each interaction you make through that profile actually double as a source of data for Facebook’s mapping algorithms. What they’re trying to do is determine the structure of the network: where the cliques are, which people bridge them, who knows who.
Once Facebook knows the structure of your social network, it can analyze it to predict not only the people you’re most likely to know now, but the people you’re most likely to know in the future.
(Via Daily Times)