Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.
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 analyzed reviews to verify trustworthiness.
I only received one of the two books pictured on the item's page. That picture needs to be changed. I tried to look for a way to contact someone to get reimbursed but it wasn't easy like it is with a non-digital product.