How to fix Amazon reviews: let me count the ways

Amazon introduced its five star customer ratings system over two decades ago as a way to improve clickthrough and sales. At first, each book’s rating was the pure average of all its customer reviews. But no one ever said that system was perfect.

Six years ago there was a widespread scandal of ‘sockpuppetry’ in the world of book reviews. Then, three years ago, Amazon sued four sites selling reviews for pay, and began using machine learning to give books a weighted average biased in favour of n...