If you’ve used Facebook for a while, you know that sometime about a year ago the social network updated its “stream” to stop showing everything everyone you know posted, and instead magically began listing only items you might find interesting. The magic was a filter — a process Facebook calls EdgeRank. In essence, EdgeRank creates a score to judge whether something someone else creates is worth pushing to your news stream, multiplying the affinity between you and the creator by the “weight” of the type of change (e.g. a comment is worth more than a “like” click), and also by the recency of when the change was made. If your girlfriend made a long comment a minute ago, bingo, up to the top. That long-lost cousin you rarely chat with, boom, off the page.
When Facebook first started culling its news feed, technologist Robert Scoble was an immediate fan, writing (and we paraphrase) that the filter made his feed instantly warmer — tapping a more relevant, lifelike view of his contacts. But think more deeply about it, and it is startling that Facebook admits its own network was filled with so much chaff that shoddy material must be eliminated. Metcalfe was wrong when he supposed that the value of a network grows exponentially based on its number of nodes, because he failed to see that each point is not created equal, and the data flowing between them also has differing levels of quality. Marketers who hope messages can go viral inside new human networks may hit a wall if the users of such networks find filters are necessary to wall off the content they find irrelevant. Perhaps, just as the automobile amplified daily pedestrian travel, new communication technologies have reset our ability to maintain relationships at a higher level — but like your new commute to work, it’s only a set distance further, not an exponential growth curve to the horizon.