How Hacker News ranking algorithm works
Some weaknesses of this algorithm are:<p>(1) Wall-clock hours penalize an article even if no one is reading (overnight, for example). A time denominated in ticks of actual activity (such as views of the 'new' page, or even upvotes-to-all-submissions) might address this.<p>(2) An article that misses its audience first time through -- perhaps due to (1) or a bad headline -- may never recover, even with a later flurry of votes far beyond what new submissions are getting.<p>Without checking the exact numbers, consider a contrived example: Article A is submitted at midnight and 3 votes trickle in until 8am. Then at 8am article B is submitted. Over the next hour, B gets 6 votes and A gets 9 votes. (Perhaps many of those are duplicate-submissions that get turned into upvotes.) A has double the total votes, and 50% more votes even in the shared hour, but still may never rank above B, because of the drag of its first 8 hours.<p>(I think you'd need to timestamp each vote for an improved decay function.)