So, Amazon has: "People who bought this book bought some of these other five books." This 'recommendation' only requires simple counting and nothing like 'cor

So, Amazon has: "People who bought this book bought some of these other five books." This 'recommendation' only requires simple counting and nothing like 'correlation'. The technique has some pros and cons. I can believe that the technique is helpful for shoppers, but it's a bit too weak for a recommendation engine.