Five and a half years ago, Netflix offered data and a $1 million prize to improve their recommendation system by at least ten percent. In 2009, a statistics team at AT&T Labs, BellKor, did that. Unfortunately, Netflix never integrated the algorithm into production.
If you followed the Prize competition, you might be wondering what happened with the final Grand Prize ensemble that won the $1M two years later. This is a truly impressive compilation and culmination of years of work, blending hundreds of predictive models to finally cross the finish line. We evaluated some of the new methods offline but the additional accuracy gains that we measured did not seem to justify the engineering effort needed to bring them into a production environment. Also, our focus on improving Netflix personalization had shifted to the next level by then.
That's too bad. Netflix knows their business better than anyone, but I sure wish Keeping Up with the Kardashians wasn't listed in my top 10 right now.