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Hmm... so the rating increases exponentially, by an order of magnitude every 12.5 hours?

Doesn't that mean that the number of points for a new post requires a something like a 5 megabyte sized int to be stored in memory?

Or did I misunderstand this?




No, ratings don't change without votes being cast. But new posts automatically start out with a higher rating, so a post must grow its (positive) vote differential by 10x to "keep up" with the new posts. The rating increases as a log of the vote differential, so the votes need to increase exponentially, not the rating. The vote differential increasing by 100x would result in an increase of 2 rating points (this is what a logarithm means).

A new post submitted on June 8, 2008 would have started out with about 1753 rating points, and this number grows by a little less than 2 every day. So it's not that big to store.

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d'oh. Thanks. My brain must not have been screwed on right while I was reading this.

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No. The rating doesn't change unless people vote on it, and is a function of the logarithm of number of votes.

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