Order by Recommended doesn't work
I click 'sort by recommended' and I get all kinds of predicted ratings at the top, it should go from highest to lowest, but it's all over the place.
This is, currently, the intended behavior of our recommender -- the key idea here is that we think of "predicted rating" and "recommendation" as two separate ideas -- there's more to forming good recommendations than just filling it up with things we predict a person will like if they watch. For instance -- if the recommendation is full of things that the user is unlikely to watch (even if they would rate it highly *if* they did watch it) then it's not a good recommendation is it? An example of this might be recommendations full of obscure, or hard-to-find movies. Another common example is a recommendation full of only one thing (like, recommending only "star trek" movies -- there's enough to fill a page of recommendations, but after recommending one or two, there isn't actually much point recommending the rest *at the same time*)
To try to avoid this, we make the "recommendation" system slightly different form the prediction system by adding in a customizable amount of popularity. Each user can make their recommendations bias towards, or away from, popular items which distorts the recommendation order slightly away-from true prediction order, but tends to improve the overall quality of recommendations. By default this is a pretty small effect -- it would only change the sorting if there is a big difference in popularity, or a big difference in predicted value I would think, but you can make it stronger, or even a little weaker.
If you're finding you're not happy with the recommendation order you have right now, it might be worth adjusting it slightly using the "star menu" in the top-right of MovieLens. From that menu click the "configure" link for whichever algorithm you wish to use.
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Benjamin Katenkamp commented
I think what the Admin said should be an option, not the default. Then again, It's conflicting, because if it's recommending something and telling us the prediction is like 3 star on the 3rd page, then one of them is incorrect, if it's sorted by what I want over higher predicted ratings. If I go to page 65 and find a 4.5 star one and then I watch it and I love it, then the predicted rating isn't doing me any favors because unless I go to page 65 I'll keep watching predicted ratings of 3 stars because the page recommended it.