http://en.wikipedia.org/wiki/H-index
the variation for Hacker News:
A HNer has index h:
if h of [his/her] posts have at least h upvotes, and the rest posts have at most h upvotes each.
the variation for Hacker News:
A HNer has index h:
if h of [his/her] posts have at least h upvotes, and the rest posts have at most h upvotes each.