To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
Much of what is covered in this book is explored in greater depth in the Ellipsis Manual. If you could only select 1 book, I would suggest the Ellipsis Manual as it’s a much bigger bang for your buck and goes into much more detail of behavioral analysis.