Hacker News's ranking algorithm isn't public, is it?
At least, it probably isn't in our version of news.arc. As Paul Graham says at http://arclanguage.org/item?id=12468, "I should release a new version though. News.arc is greatly improved since the last release." (I assume the ranking algorithm wouldn't escape scrutiny....)
I noticed that a few pieces of the algorithm were not released, and the algorithm has surely changed since arc3.1, but the published code explains at least the overall behavior of Hacker News ranking.
