The Race to Build a PageRank for the Social Web Continues

As the race to build the social version of Google’s PageRank (s goog) heats up, PeerIndex has added a new source of data for its rankings: the company said today that users can now connect their Quora profiles to the service, which will use their activity at the popular question-and-answer site — including any votes that their answers get from other Quora users — as another tool to measure their authority on various topics. As we’ve discussed before at GigaOM, companies like PeerIndex and Klout are trying to become the default measure of online influence, something that advertisers and marketers in particular are extremely interested in as they try to identify “influencers” who can spread their messages.

Both PeerIndex and Klout rank users based on data that comes from their Twitter, Facebook and LinkedIn accounts, although the two sites describe their rankings somewhat differently. Klout talks about overall “reach” and “amplification,” both of which are determined by looking at a user’s activity and how much impact it has on their social graph — whether their tweets are re-tweeted by others with influence, for example. PeerIndex says that it looks at a user’s activity in Twitter, Facebook and LinkedIn and then comes up with an authority rank for their expertise in eight topic areas, which it uses to create an influence “footprint” for each user.

Unlike Klout, PeerIndex also ranks what it calls “realness,” which is a measure of the likelihood that a user is an actual person rather than an automated feed or “spambot” (luckily, PeerIndex seems pretty convinced that I am a real person). And if a user has a huge number of followers but many of those are bots, the company says that actually decreases their overall ranking.

The focus on authority within specific topic areas makes Quora a particularly good fit for PeerIndex, since the Q&A site is building a crowdsourced ranking system of its own that measures the authority of different users, something Quora co-founder Charlie Cheever talked about recently. Although he didn’t give any details, that authority ranking presumably looks at the quality of a user’s answers and any votes or comments that they have gotten from other users. That kind of influence makes Quora results a perfect addition to a service like PeerIndex — in the same way that StackOverflow is now using content from its Q&A site as a way of ranking users as part of its new careers service.

We’re also starting to see some interesting applications of the data that comes from Klout and PeerIndex. For one thing, companies are starting to offer perks to Klout users who have high scores — including discounts at retail outlets and advance screenings of movies, presumably because marketers are hoping these “influencers” will spread the news to their followers and social graphs. And Peersquare is a recently-launched blend of PeerIndex and the Foursquare location-based service that shows the rankings of people who are in the same location as you, something that could be useful during a conference or other event. Marc Benioff of (s crm) has even talked about compensating employees based on their influence within social networks.

As Klout and PeerIndex add more sources of reputation or influence data such as Quora to their rankings, the web moves closer to having a kind of Google PageRank for social activity, with all that implies. The big problem, as with Google search, is how to exclude the social equivalent of black-hat SEO and link spam, and how to determine what it is real influence and what is simply Justin Bieber-style popularity.

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Post and thumbnail courtesy of Flickr user Danny Cain