Heading Facebook’s effort to figure out what can be learned from all our data is Cameron Marlow, a tall 35-year-old who until recently sat a few feet away from Zuckerberg. The group Marlow runs has escaped the public attention that dogs Facebook’s founders and the more headline-grabbing features of its business. Known internally as the Data Science Team, it is a kind of Bell Labs for the social-networking age. The group has 12 researchers—but is expected to double in size this year. They apply math, programming skills, and social science to mine our data for insights that they hope will advance Facebook’s business and social science at large. Whereas other analysts at the company focus on information related to specific online activities, Marlow’s team can swim in practically the entire ocean of personal data that Facebook maintains. Of all the people at Facebook, perhaps even including the company’s leaders, these researchers have the best chance of discovering what can really be learned when so much personal information is compiled in one place.
Facebook has all this information because it has found ingenious ways to collect data as people socialize. Users fill out profiles with their age, gender, and e-mail address; some people also give additional details, such as their relationship status and mobile-phone number. A redesign last fall introduced profile pages in the form of time lines that invite people to add historical information such as places they have lived and worked. Messages and photos shared on the site are often tagged with a precise location, and in the last two years Facebook has begun to track activity elsewhere on the Internet, using an addictive invention called the “Like” button. It appears on apps and websites outside Facebook and allows people to indicate with a click that they are interested in a brand, product, or piece of digital content. Since last fall, Facebook has also been able to collect data on users’ online lives beyond its borders automatically: in certain apps or websites, when users listen to a song or read a news article, the information is passed along to Facebook, even if no one clicks “Like.” Within the feature’s first five months, Facebook catalogued more than five billion instances of people listening to songs online. Combine that kind of information with a map of the social connections Facebook’s users make on the site, and you have an incredibly rich record of their lives and interactions.