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    Lobsters’ ranking formula is quite different from the one in this article. Ordering of stories on the home page accounts for the stories’ tags and comment scores in addition to their scores and ages. Here is a simplified version of the formula:

    hotness = -( log(story_votes+story_comment_votes) + age + bonuses_or_penalties_for_certain_tags )

    That formula comes from Story#calculated_hotness. “Hotness” is used to sort stories on the home page (HomeController#index calling StoryRepository#hottest).

    Stories on Lobsters’ Recent page, on the other hand, are ordered using a different algorithm, in StoryRepository#recent. That ordering tries to “help recently-submitted stories that didn’t gain traction”.

    There are unit tests for both sorting algorithms.

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      I have seen tags with bonuses, but not penalties. Are there any tags currently with a penalty or is it just that the system can handle penalties?

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        They are all shown at https://lobste.rs/filters and some have a negative mod.

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          Heh, for some reason I thought [ask] had a bonus. Guess you learn something every day.

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            Because comments count towards the hotness value, tags that usually generate a lot of discussion are penalized just so those stories don’t stay at #1 for days on end.