Two points: It seems a question of scope is in order here; what exactly is the purpose of a recommendation system? Is it a system to forward to users that wh

Two points: It seems a question of scope is in order here; what exactly is the purpose of a recommendation system? Is it a system to forward to users that which they want to see, or is it a system that suggests various opinion of high quality to users? Often, I think we're trying to construct the latter by designing the former. Secondly, Reddit's system works perfectly to forward to the user what they would like based on what's been submitted - the issue being that the average quality of submission has lowered over time. Even if the system gives you the best POS, you're still stuck with a POS. The solution: Scaling is the problem, so stop/limit scaling. We're not seeing a degradation of quality, we're seeing a better reflection of the average opinion - the larger the crowd, the lower the average. We're trying to enforce an expectation of quality that is held by a few on the many; this is impossible! The many don't hold the same regard or opinions as the few. You can tweak things a little, perhaps come up with systems that use more cpu power than the space navigation does, but the end result will be the same: average opinion wins - exactly what you should expect. Average opinion isn't what we want though, is it?