General Discussion
In reply to the discussion: DU doesn't need fewer regular posters in GD. [View all]MineralMan
(146,384 posts)posts in a three-hour period. It's an automated thing, I believe. After three hours, posts disappear from the Trending list. It's not uncommon for posts with as few as 15 recommendations to appear on the list, but it's usually more than that.
So, it's not a person who picks them. It's an algorithm.
Beyond that basic selection method, I don't know if there is any human input into it. I believe that two posts by the same DUer won't appear on the list at the same time. I base that on a couple of my posts in several instances that had enough recommendations, but only one appeared on the list during the same 3-hour period.
I believe this is correct, but I don't actually have any access to any of the site's algorithms, so I could be incorrect. I'm basing this on my own experience with that list.
The Greatest Threads list works much the same way, but more posts are included and there's a 24-hour window.