This is a really interesting book about allowing users to provide feedback/ratings on your content or services, including common algorithms for calculating those ratings, the value of each user's ratings, and how to manage this information. I found this very enlightening, as many of the ideas discussed in this book hadn't initially occurred to me.



Perhaps the most useful material, in my opinion, was the discussion around different reputation models. Included in the discussion were the models used by eBay, Yahoo!, Slashdot, and others. Also very valuable were the algorithms for tabulating ratings and reputation so that performance is not impacted.



I found the information in this book invaluable in building online rating systems. If you're working on such a project, I'd highly recommend checking out this book.