Quora’s New Algorithm for Ranking Answers

The Q&A site Quora has detailed its plans for a PageRank, of sorts, for answers submitted to the site. In a nutshell, “good answers” from those who consistently write “good answers” will rank higher than others’ responses.

Quora co-founder Charlie Cheever hinted at the changes in a post last month, following Quora’s explosive growth over the holidays. “We’re developing an algorithm to determine user quality. The algorithm is somewhat similar to PageRank,” Cheever wrote, noting that ranking people’s responses is a slightly different problem than ranking Web pages.

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That ranking “problem” made headlines last weekend when tech evangelist Robert Scoble retracted his initial enthusiastic endorsement of Quora (Is Quora the Biggest Blogging Innovation in 10 Years?, written December 26, 2010), with a post arguing that he’d “been wrong” about Quora’s potential. Scoble protested the up- and downvoting of the site, in no small part because his answers weren’t getting the spotlight he felt they deserved.

An Algorithm for Good Answers

Yesterday, Quora’s other co-founder, Adam D’Angelo, gave more details about the site’s plans for improving its answer ranking system.

• Answers with more upvotes are ranked higher.
• Answers with more downvotes are ranked lower.
• A vote from a user who has written good answers in the past carries more weight (both upvotes and downvotes).
• Answers written by users who have written good answers in the past will be ranked higher.
• Votes from people detected to be gaming the system (vote collusion, spam, bullying, etc.) will be ignored or minimized. This is also against policy and may result in a ban.
• Whether a user is an admin or reviewer does not affect the scores in this system.

“Basically, if you want your votes to have more weight,” writes D’Angelo, “the best thing to do is to write good answers.”

Will this settle the debate about what constitutes a “good answer” or whose answers are “useful”? And will it address some of the issues surrounding the power of “old-timers” on the site and those who are new to Quora (whether there via Scoble’s influence or not)?

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