So I tried to work on Gravity's training algorithm for Patarek's NSVD1 recommender. And utterly failed. I'm either reading it wrong, typing wrong, or not understanding the notation, but it's supposed to give me a RMSE of 0.9344, but mine has gone between. 1.013 and 2 something. Yeah...

So I'm going to be redoing that one. Hopefully after getting that working, I can do the Hybrid and then finally get on to a few of my own modifications. I only need to figure out what they should be.